Bar Exam (Uniform) Quiz: Multi Party Liability
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Multi Party LiabilityQuestion 1 of 20

In a jurisdiction with pure comparative negligence and joint and several liability, a plaintiff's damages are assessed at $100,000. A jury apportions fault as follows: Plaintiff 20%, Defendant 1 50%, and Defendant 2 30%. The plaintiff decides to sue only Defendant 1.

What is the maximum amount the plaintiff can recover from Defendant 1? Select one.

$50,000.
$70,000.
$80,000.
$100,000.
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Bar Exam (Uniform) Quiz

Bar Exam (Uniform) Quiz: Multi Party Liability

Practice Multi Party Liability in Bar Exam (Uniform) with focused quiz questions that help you check what you know, review explanations, and build confidence with test-style prompts.

What this quiz covers

This quiz focuses on Multi Party Liability, giving you a quick way to practice the rules, question types, and explanations that matter most for Bar Exam (Uniform).

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

All questions

Question 1

In a jurisdiction with pure comparative negligence and joint and several liability, a plaintiff's damages are assessed at $100,000. A jury apportions fault as follows: Plaintiff 20%, Defendant 1 50%, and Defendant 2 30%. The plaintiff decides to sue only Defendant 1.

What is the maximum amount the plaintiff can recover from Defendant 1? Select one.

  1. $50,000.
  2. $70,000.
  3. $80,000. (correct answer)
  4. $100,000.
Explanation: The correct answer is $80,000. First, the plaintiff's total recovery is reduced by their own percentage of fault (20%). Thus, the total recoverable damages are $100,000 - (20% of $100,000) = $80,000. Second, under joint and several liability, the plaintiff can recover the entire amount of their recoverable damages from any single defendant. Therefore, the plaintiff can recover the full $80,000 from Defendant 1, who can then seek contribution from Defendant 2.

Question 2

A patient was injured due to the negligence of two physicians, a surgeon and an anesthesiologist, during a single operation. The patient's damages are $1 million. The jurisdiction applies joint and several liability. The patient sued only the surgeon and recovered the full $1 million. A jury determined that the surgeon was 60% at fault and the anesthesiologist was 40% at fault.

What is the surgeon's best recourse against the anesthesiologist? Select one.

  1. Sue for indemnification for the entire $1 million judgment.
  2. Sue for contribution for $500,000, representing half of the total liability.
  3. The surgeon has no recourse because she was also found to be at fault.
  4. Sue for contribution for $400,000, representing the anesthesiologist's share of liability. (correct answer)
Explanation: Joint and several liability questions test your understanding of how defendants can recover from each other after one pays more than their proportionate share. When multiple defendants are jointly and severally liable, the plaintiff can collect the full judgment from any defendant, but that defendant can then seek contribution from the others. The surgeon paid the entire $1 million judgment but was only 60% at fault. Under contribution principles, each defendant should ultimately bear responsibility only for their proportionate share of the fault. Since the anesthesiologist was found 40% at fault, the surgeon can recover 400,000fromtheanesthesiologistthroughcontribution(400,000 from the anesthesiologist through contribution (1 million × 40% = $400,000). This leaves the surgeon bearing $600,000, which matches his 60% fault percentage. Answer A is wrong because indemnification involves one party paying the entire amount to another, typically when one party bears no fault or has a contractual right to full reimbursement. Here, the surgeon was also at fault, so partial contribution, not full indemnification, applies. Answer B incorrectly suggests splitting the liability equally regardless of fault percentages. Contribution is based on each party's actual degree of fault, not an automatic 50-50 split. Answer C misunderstands contribution law. The fact that the surgeon was also negligent doesn't eliminate the right to contribution—it just means the surgeon cannot recover the entire amount through indemnification. Remember: In joint and several liability cases, look for the fault percentages to determine contribution amounts. Each defendant ultimately pays their proportionate share, regardless of who initially paid the judgment.

Question 3

Two factories independently discharged pollutants into a river, which contaminated a downstream farm's water supply, causing a single, indivisible injury to the farm's crops. The farm owner sued both factory owners. It is impossible for the farm owner to prove what proportion of the damage was caused by each factory.

In a jurisdiction applying traditional common law principles, what is the most likely result? Select one.

  1. Both factories will be held jointly and severally liable for the entire damage to the farm's crops. (correct answer)
  2. Each factory will be held liable for 50% of the damages under the alternative liability doctrine.
  3. The case will be dismissed because the farm owner cannot meet the burden of proving causation for either defendant.
  4. Liability will be imposed under a market share theory based on each factory's production output.
Explanation: This question tests your understanding of joint and several liability in tort law, specifically when multiple defendants cause indivisible harm. When you encounter pollution cases with multiple sources causing a single injury, think about how courts handle the burden of proof for causation. Under traditional common law principles, when two or more defendants act independently but cause indivisible harm, courts apply joint and several liability. Here, both factories contributed to the contamination that caused one unified crop injury. Even though the farm owner cannot prove each factory's specific contribution, the harm is clearly linked to both defendants' conduct. This shifts the burden to the defendants to prove their respective contributions - if they cannot, each remains liable for the entire damages. This doctrine protects plaintiffs from the unfairness of losing their case simply because multiple wrongdoers made it impossible to apportion fault. Option B incorrectly applies alternative liability, which is used when only one of several defendants actually caused the harm (like in hunting accident cases), not when both clearly contributed. Option C misunderstands the causation standard - the farm owner can prove both factories caused the pollution; they just cannot quantify each contribution. This doesn't defeat causation entirely. Option D references market share liability, a modern theory primarily used in mass tort cases involving fungible products like drugs, not applicable to traditional common law or typical pollution scenarios. Remember: Joint and several liability protects plaintiffs when multiple defendants create indivisible harm. Don't confuse this with alternative liability (one actual wrongdoer among several) or market share theories (modern mass tort doctrine).

Question 4

A plaintiff was injured in an accident and sustained damages of $200,000. In a jurisdiction with a modified comparative negligence rule (plaintiff recovers if fault is not as great as defendants' combined fault), a jury apportions fault as follows: Plaintiff 50%, Defendant 1 30%, and Defendant 2 20%. The jurisdiction retains joint and several liability.

What is the total amount the plaintiff is entitled to recover? Select one.

  1. $200,000.
  2. $100,000.
  3. $60,000.
  4. $0. (correct answer)
Explanation: The correct answer is $0. The jurisdiction has a '50% bar' or 'not as great as' rule for modified comparative negligence. This means a plaintiff can only recover if their percentage of fault is less than the combined fault of the defendants. Here, the plaintiff's fault is 50%, and the defendants' combined fault is 30% + 20% = 50%. Because the plaintiff's fault (50%) is not 'less than' the defendants' fault (50%), the plaintiff is completely barred from recovery.

Question 5

Two defendants, Company X and Company Y, are found jointly and severally liable for a $200,000 injury to a plaintiff. A jury finds Company X 75% at fault and Company Y 25% at fault. Before trial, Company Y enters into a good-faith settlement with the plaintiff for $30,000. The jurisdiction's law provides that a good-faith settlement extinguishes all claims for contribution against the settling party and reduces the plaintiff's claim against the non-settling parties by the amount of the settlement.

What is the maximum amount the plaintiff can now recover from Company X after a trial? Select one.

  1. $150,000.
  2. $170,000. (correct answer)
  3. $200,000.
  4. $50,000.
Explanation: The correct answer is $170,000. In most jurisdictions that follow this rule, the plaintiff's total claim against the remaining tortfeasors is reduced by the dollar amount of the settlement, not by the settling tortfeasor's percentage of fault. Here, the total liability is $200,000. The plaintiff's claim is reduced by the $30,000 settlement amount, leaving a maximum potential recovery of $170,000 from Company X. Company X loses its right to seek contribution from Company Y.

Question 6

A homeowner suffered property damage from a fire. An investigation revealed two independent causes: a faulty electrical wire installed by an electrician and a gas leak from a line installed by a plumber. Either cause alone would have been sufficient to start the fire and cause the full extent of the damage. The homeowner sued both the electrician and the plumber.

In a jurisdiction applying the 'substantial factor' test for actual causation, what is the likely outcome? Select one.

  1. Both parties' negligence will be considered an actual cause, and they will be held jointly and severally liable. (correct answer)
  2. Only the party whose negligence occurred first in time is liable.
  3. Neither party is liable because the 'but-for' test for causation fails for both.
  4. The homeowner must choose one party to sue, as recovery from both would constitute a windfall.
Explanation: When you encounter a tort question involving multiple independent causes that each could have caused the entire harm, you're dealing with a classic causation problem where the traditional "but-for" test breaks down. The substantial factor test was developed specifically for situations like this. Under this approach, when two or more independent causes are each sufficient to produce the entire harm, courts ask whether each defendant's conduct was a "substantial factor" in bringing about the damage. Here, both the faulty electrical wire and the gas leak were substantial factors—each was sufficient to cause the complete fire damage. Therefore, both the electrician and plumber will be held liable as actual causes, and they'll face joint and several liability, meaning the homeowner can collect the full judgment from either party. This is answer A. Answer B is wrong because timing doesn't determine liability when dealing with substantial factors—both causes contributed meaningfully regardless of sequence. Answer C incorrectly focuses on the but-for test, which indeed fails here (you can't say "but for" either cause, the damage wouldn't have occurred), but that's exactly why courts use the substantial factor test instead. Answer D misunderstands the law—there's no "windfall" problem when multiple parties are each fully responsible for the same indivisible harm. Remember: when you see independent concurrent causes that are each sufficient to cause the entire harm, think "substantial factor test." The but-for test fails in these scenarios, so courts switch to this alternative approach to avoid letting clearly negligent parties escape liability.

Question 7

A patient suffered an indivisible injury as a result of the consecutive negligence of two physicians. First, a surgeon negligently performed an operation. A week later, a second physician negligently prescribed post-operative medication that worsened the patient's condition. The patient sued both physicians. The jurisdiction applies joint and several liability.

For what portion of the patient's total damages is the surgeon potentially liable? Select one.

  1. Only for the initial harm caused by the surgery, as the second physician's negligence was a superseding cause.
  2. Only for a portion of the damages equal to the surgeon's percentage of fault.
  3. For the entire amount of the patient's damages, including the aggravation caused by the second physician. (correct answer)
  4. For 50% of the damages, with the other 50% being the sole responsibility of the second physician.
Explanation: The correct answer is C. An initial tortfeasor is liable not only for the direct harm they cause but also for any foreseeable intervening forces, including subsequent medical negligence that aggravates the injury. The negligence of the second physician in treating the original injury is considered a foreseeable risk of the surgeon's initial negligence. Therefore, the surgeon is jointly and severally liable with the second physician for the full extent of the patient's ultimate harm.

Question 8

Two drivers were engaged in an illegal drag race on a city street. One of the drivers lost control of his vehicle and crashed into a legally parked car, causing extensive damage. The second driver involved in the race did not make contact with any person or property. The owner of the parked car sued both drivers.

What is the strongest legal theory for holding the second driver, who did not cause any direct impact, liable for the damage? Select one.

  1. Res ipsa loquitur, because the accident would not have occurred without negligence.
  2. Alternative liability, because it is unclear which driver's speed created the danger.
  3. Concert of action, because the second driver was participating in a common tortious design. (correct answer)
  4. Vicarious liability, because the drivers formed a temporary joint venture.
Explanation: The correct answer is concert of action. This theory imposes liability on a person who aids or encourages another to commit a tort. By participating in the drag race, an inherently dangerous and tortious activity, the second driver encouraged the first driver's negligent conduct. Both are considered to be acting in concert and can be held jointly and severally liable for the resulting harm.

Question 9

A patient was injured due to the negligence of two physicians, a surgeon and an anesthesiologist, during a single operation. The patient's damages are $1 million. The jurisdiction applies joint and several liability. The patient sued only the surgeon and recovered the full $1 million. A jury determined that the surgeon was 60% at fault and the anesthesiologist was 40% at fault.

What is the surgeon's best recourse against the anesthesiologist? Select one.

  1. Sue for indemnification for the entire $1 million judgment.
  2. Sue for contribution for $500,000, representing half of the total liability.
  3. The surgeon has no recourse because she was also found to be at fault.
  4. Sue for contribution for $400,000, representing the anesthesiologist's share of liability. (correct answer)
Explanation: Joint and several liability questions test your understanding of how defendants can recover from each other after one pays more than their proportionate share. When multiple defendants are jointly and severally liable, the plaintiff can collect the full judgment from any defendant, but that defendant can then seek contribution from the others. The surgeon paid the entire $1 million judgment but was only 60% at fault. Under contribution principles, each defendant should ultimately bear responsibility only for their proportionate share of the fault. Since the anesthesiologist was found 40% at fault, the surgeon can recover 400,000fromtheanesthesiologistthroughcontribution(400,000 from the anesthesiologist through contribution (1 million × 40% = $400,000). This leaves the surgeon bearing $600,000, which matches his 60% fault percentage. Answer A is wrong because indemnification involves one party paying the entire amount to another, typically when one party bears no fault or has a contractual right to full reimbursement. Here, the surgeon was also at fault, so partial contribution, not full indemnification, applies. Answer B incorrectly suggests splitting the liability equally regardless of fault percentages. Contribution is based on each party's actual degree of fault, not an automatic 50-50 split. Answer C misunderstands contribution law. The fact that the surgeon was also negligent doesn't eliminate the right to contribution—it just means the surgeon cannot recover the entire amount through indemnification. Remember: In joint and several liability cases, look for the fault percentages to determine contribution amounts. Each defendant ultimately pays their proportionate share, regardless of who initially paid the judgment.

Question 10

A plaintiff sustained $500,000 in damages in an accident. A jury apportioned fault as follows: Plaintiff 10%, Defendant A 60%, and Defendant B 30%. The jurisdiction applies pure comparative negligence and joint and several liability. The plaintiff collected the entire recoverable judgment of $450,000 from Defendant A.

How much can Defendant A recover in contribution from Defendant B? Select one.

  1. $135,000.
  2. $150,000. (correct answer)
  3. $225,000.
  4. $300,000.
Explanation: The correct answer is $150,000. Contribution is based on each tortfeasor's equitable share of the total damages, not the judgment amount paid by the plaintiff. Defendant B was found 30% at fault for the total damages of $500,000. Therefore, Defendant B's equitable share of the liability is 30% of $500,000, which equals $150,000. Since Defendant A paid the full recoverable amount, which included Defendant B's share, Defendant A is entitled to contribution from Defendant B for that amount.

Question 11

A homeowner suffered property damage from a fire. An investigation revealed two independent causes: a faulty electrical wire installed by an electrician and a gas leak from a line installed by a plumber. Either cause alone would have been sufficient to start the fire and cause the full extent of the damage. The homeowner sued both the electrician and the plumber.

In a jurisdiction applying the 'substantial factor' test for actual causation, what is the likely outcome? Select one.

  1. Both parties' negligence will be considered an actual cause, and they will be held jointly and severally liable. (correct answer)
  2. Only the party whose negligence occurred first in time is liable.
  3. Neither party is liable because the 'but-for' test for causation fails for both.
  4. The homeowner must choose one party to sue, as recovery from both would constitute a windfall.
Explanation: When you encounter a tort question involving multiple independent causes that each could have caused the entire harm, you're dealing with a classic causation problem where the traditional "but-for" test breaks down. The substantial factor test was developed specifically for situations like this. Under this approach, when two or more independent causes are each sufficient to produce the entire harm, courts ask whether each defendant's conduct was a "substantial factor" in bringing about the damage. Here, both the faulty electrical wire and the gas leak were substantial factors—each was sufficient to cause the complete fire damage. Therefore, both the electrician and plumber will be held liable as actual causes, and they'll face joint and several liability, meaning the homeowner can collect the full judgment from either party. This is answer A. Answer B is wrong because timing doesn't determine liability when dealing with substantial factors—both causes contributed meaningfully regardless of sequence. Answer C incorrectly focuses on the but-for test, which indeed fails here (you can't say "but for" either cause, the damage wouldn't have occurred), but that's exactly why courts use the substantial factor test instead. Answer D misunderstands the law—there's no "windfall" problem when multiple parties are each fully responsible for the same indivisible harm. Remember: when you see independent concurrent causes that are each sufficient to cause the entire harm, think "substantial factor test." The but-for test fails in these scenarios, so courts switch to this alternative approach to avoid letting clearly negligent parties escape liability.

Question 12

A bouncer at a tavern, an employee of the tavern, became angry with a patron and used excessive force while ejecting him, causing serious injury. The tavern had a strict policy against using excessive force, and the bouncer had been specifically trained on this policy. The patron sued the tavern for his injuries.

Is the tavern likely to be held liable for the bouncer's intentional tort? Select one.

  1. No, because employers are generally not vicariously liable for the intentional torts of their employees.
  2. No, because the bouncer's actions were in direct violation of the tavern's explicit policy and training.
  3. Yes, because the bouncer's actions, though excessive, arose out of and were related to his employment duties. (correct answer)
  4. Yes, but only if the patron can prove that the tavern was negligent in hiring or supervising the bouncer.
Explanation: The correct answer is yes. An employer can be held vicariously liable for an employee's intentional tort if the tort was committed within the scope of employment. For jobs that involve the use of force, like a bouncer, using excessive force is often seen as a misguided attempt to serve the employer's interests. The act of ejecting a patron is part of the job, so the excessive manner in which it was done does not automatically take it outside the scope of employment. Violating a company policy is not a complete defense.

Question 13

A plaintiff sustained $500,000 in damages in an accident. A jury apportioned fault as follows: Plaintiff 10%, Defendant A 60%, and Defendant B 30%. The jurisdiction applies pure comparative negligence and joint and several liability. The plaintiff collected the entire recoverable judgment of $450,000 from Defendant A.

How much can Defendant A recover in contribution from Defendant B? Select one.

  1. $135,000.
  2. $150,000. (correct answer)
  3. $225,000.
  4. $300,000.
Explanation: The correct answer is $150,000. Contribution is based on each tortfeasor's equitable share of the total damages, not the judgment amount paid by the plaintiff. Defendant B was found 30% at fault for the total damages of $500,000. Therefore, Defendant B's equitable share of the liability is 30% of $500,000, which equals $150,000. Since Defendant A paid the full recoverable amount, which included Defendant B's share, Defendant A is entitled to contribution from Defendant B for that amount.

Question 14

A construction worker was injured when a scaffold collapsed. The worker sued the general contractor and the scaffolding subcontractor. A jury determined the worker's total damages were $500,000 and apportioned fault as follows: 80% to the subcontractor for negligent assembly and 20% to the general contractor for negligent supervision. The jurisdiction applies pure several liability.

If the subcontractor is bankrupt and unable to pay any portion of the judgment, what is the maximum amount the worker can recover from the general contractor? Select one.

  1. $0, because the subcontractor was primarily at fault.
  2. $100,000. (correct answer)
  3. $250,000.
  4. $500,000.
Explanation: The correct answer is $100,000. In a jurisdiction with pure several liability (also known as proportionate share liability), each defendant is liable only for their respective percentage of the plaintiff's damages. The general contractor was found 20% at fault, so its liability is limited to 20% of the $500,000 damages, which is $100,000. The plaintiff bears the risk that one of the defendants may be insolvent.

Question 15

Two defendants, Company X and Company Y, are found jointly and severally liable for a $200,000 injury to a plaintiff. A jury finds Company X 75% at fault and Company Y 25% at fault. Before trial, Company Y enters into a good-faith settlement with the plaintiff for $30,000. The jurisdiction's law provides that a good-faith settlement extinguishes all claims for contribution against the settling party and reduces the plaintiff's claim against the non-settling parties by the amount of the settlement.

What is the maximum amount the plaintiff can now recover from Company X after a trial? Select one.

  1. $150,000.
  2. $170,000. (correct answer)
  3. $200,000.
  4. $50,000.
Explanation: The correct answer is $170,000. In most jurisdictions that follow this rule, the plaintiff's total claim against the remaining tortfeasors is reduced by the dollar amount of the settlement, not by the settling tortfeasor's percentage of fault. Here, the total liability is $200,000. The plaintiff's claim is reduced by the $30,000 settlement amount, leaving a maximum potential recovery of $170,000 from Company X. Company X loses its right to seek contribution from Company Y.

Question 16

In a jurisdiction with pure comparative negligence and joint and several liability, a plaintiff's damages are assessed at $100,000. A jury apportions fault as follows: Plaintiff 20%, Defendant 1 50%, and Defendant 2 30%. The plaintiff decides to sue only Defendant 1.

What is the maximum amount the plaintiff can recover from Defendant 1? Select one.

  1. $50,000.
  2. $70,000.
  3. $80,000. (correct answer)
  4. $100,000.
Explanation: The correct answer is $80,000. First, the plaintiff's total recovery is reduced by their own percentage of fault (20%). Thus, the total recoverable damages are $100,000 - (20% of $100,000) = $80,000. Second, under joint and several liability, the plaintiff can recover the entire amount of their recoverable damages from any single defendant. Therefore, the plaintiff can recover the full $80,000 from Defendant 1, who can then seek contribution from Defendant 2.

Question 17

Two drivers were engaged in an illegal drag race on a city street. One of the drivers lost control of his vehicle and crashed into a legally parked car, causing extensive damage. The second driver involved in the race did not make contact with any person or property. The owner of the parked car sued both drivers.

What is the strongest legal theory for holding the second driver, who did not cause any direct impact, liable for the damage? Select one.

  1. Res ipsa loquitur, because the accident would not have occurred without negligence.
  2. Alternative liability, because it is unclear which driver's speed created the danger.
  3. Concert of action, because the second driver was participating in a common tortious design. (correct answer)
  4. Vicarious liability, because the drivers formed a temporary joint venture.
Explanation: The correct answer is concert of action. This theory imposes liability on a person who aids or encourages another to commit a tort. By participating in the drag race, an inherently dangerous and tortious activity, the second driver encouraged the first driver's negligent conduct. Both are considered to be acting in concert and can be held jointly and severally liable for the resulting harm.

Question 18

A landowner hired an independent contractor to repair a retaining wall on her property. The contractor performed the work negligently, causing the wall to collapse and injure a neighbor. The neighbor sued the landowner, recovering a judgment based on the landowner's non-delegable duty to prevent harm from artificial conditions on her land.

What is the landowner's best claim against the independent contractor? Select one.

  1. A claim for contribution based on the contractor's percentage of fault.
  2. A claim for full indemnity because the landowner's liability was passive or vicarious. (correct answer)
  3. No claim, because the landowner's duty was non-delegable, making her primarily liable.
  4. A claim in contract for breach of warranty, but no tort claim for the judgment paid.
Explanation: The correct answer is a claim for full indemnity. Even when a duty is non-delegable (making the principal liable to the third party), the principal is typically not at fault. Their liability is vicarious or imputed by law. The party who was actively negligent, the independent contractor, is ultimately responsible. Therefore, the landowner, whose liability is passive, is entitled to full indemnification from the contractor.

Question 19

You are representing a client who was injured in a three-car accident. The first car stopped suddenly, the second car (your client's) stopped safely behind it, and the third car rear-ended your client, pushing his car into the first car. The driver of the third car is uninsured and has no assets. The driver of the first car is also claiming injuries and may sue your client.

When considering your client's potential recovery for his own injuries, what multi-party liability issue is most crucial to investigate? Select one.

  1. Whether the sudden stop by the first driver was negligent, potentially making that driver a joint tortfeasor. (correct answer)
  2. The applicability of market share liability to the manufacturers of the cars' brake systems.
  3. Whether your client can seek contribution from the third driver.
  4. The vicarious liability of the first driver's employer for the sudden stop.
Explanation: The most crucial issue for your client's recovery is identifying a solvent party to sue. Since the third driver, who was clearly at fault, is judgment-proof, the best strategy is to investigate whether the first driver also bears some responsibility for the accident. If the first driver's stop was negligent (e.g., without cause), that driver could be a joint tortfeasor, creating a source of recovery for your client. Contribution is irrelevant to your client's recovery, and there are no facts to support the other theories.

Question 20

Two factories independently discharged pollutants into a river, which contaminated a downstream farm's water supply, causing a single, indivisible injury to the farm's crops. The farm owner sued both factory owners. It is impossible for the farm owner to prove what proportion of the damage was caused by each factory.

In a jurisdiction applying traditional common law principles, what is the most likely result? Select one.

  1. Both factories will be held jointly and severally liable for the entire damage to the farm's crops. (correct answer)
  2. Each factory will be held liable for 50% of the damages under the alternative liability doctrine.
  3. The case will be dismissed because the farm owner cannot meet the burden of proving causation for either defendant.
  4. Liability will be imposed under a market share theory based on each factory's production output.
Explanation: This question tests your understanding of joint and several liability in tort law, specifically when multiple defendants cause indivisible harm. When you encounter pollution cases with multiple sources causing a single injury, think about how courts handle the burden of proof for causation. Under traditional common law principles, when two or more defendants act independently but cause indivisible harm, courts apply joint and several liability. Here, both factories contributed to the contamination that caused one unified crop injury. Even though the farm owner cannot prove each factory's specific contribution, the harm is clearly linked to both defendants' conduct. This shifts the burden to the defendants to prove their respective contributions - if they cannot, each remains liable for the entire damages. This doctrine protects plaintiffs from the unfairness of losing their case simply because multiple wrongdoers made it impossible to apportion fault. Option B incorrectly applies alternative liability, which is used when only one of several defendants actually caused the harm (like in hunting accident cases), not when both clearly contributed. Option C misunderstands the causation standard - the farm owner can prove both factories caused the pollution; they just cannot quantify each contribution. This doesn't defeat causation entirely. Option D references market share liability, a modern theory primarily used in mass tort cases involving fungible products like drugs, not applicable to traditional common law or typical pollution scenarios. Remember: Joint and several liability protects plaintiffs when multiple defendants create indivisible harm. Don't confuse this with alternative liability (one actual wrongdoer among several) or market share theories (modern mass tort doctrine).