All questions
Question 1
A university's motto reads: Veritas vos liberabit. The admissions office uses this phrase in its welcome materials, explaining to incoming students that the institution is committed to intellectual inquiry and the pursuit of knowledge as a path to freedom.
A student interprets Veritas vos liberabit as meaning 'Truth will free you (all).' Which of the following best explains why this interpretation is linguistically accurate AND why a distractor translation—'The truth has freed us'—is grammatically incorrect?
- 'Vos' is second-person plural, confirming the 'you all' reading, and liberabit is future indicative active, not perfect indicative, ruling out 'has freed'; 'nos' would be required for 'us.' (correct answer)
- 'Vos' can serve as either nominative or accusative plural, so the phrase could mean 'you all free the truth'; furthermore, liberabit functions as a perfect form in some paradigms, supporting 'has freed' once the subject is reanalyzed.
- 'Vos' is first-person plural in Latin, which explains the 'us' reading; liberabit is indeed future tense, so 'the truth will free us' is the most defensible translation—'you all' would require a different pronoun entirely.
- 'Vos' is correctly identified as second-person plural, but liberabit is a present indicative form, making the proper translation 'Truth frees you all'; the 'has freed' version fails only because of the wrong pronoun, not any issue with the verb tense.
Explanation: When you encounter a Latin translation question like this, you need to analyze two things simultaneously: pronoun identity and verb tense/form. Both must be correct for a translation to hold up.
Start with vos. In Latin, vos is unambiguously second-person plural — it means "you all" (accusative or nominative). This immediately confirms the student's reading of "you all" and eliminates any "us" interpretation, which would require nos (first-person plural). Next, examine liberabit. This is the future indicative active, third-person singular of liberare: the -bi- infix signals future tense, not perfect. The perfect active would be liberavit (he/she freed) or liberaverat (pluperfect). So "will free" is precisely right, and "has freed" cannot stand. Answer A correctly identifies both points — vos as second-person plural and liberabit as future indicative — and explains that nos would be needed for "us." This makes A the complete, accurate answer.
Answer B is wrong twice over: while vos can technically be nominative, claiming the phrase could mean "you all free the truth" ignores that veritas is nominative (the subject), and liberabit is absolutely not a perfect form in any paradigm — that claim is simply false. Answer C is dangerously wrong because it misidentifies vos as first-person plural; that's nos, not vos — a foundational pronoun error. Answer D correctly identifies vos but misreads liberabit as present indicative; the -bi- infix marks future, not present, tense.
Your study tip: memorize the -bi-/-bu- future infix for first/second conjugation verbs — it's the clearest signal distinguishing future from present and perfect forms on Latin grammar questions.
Question 2
A student is practicing the motto Dum spiro, spero, attributed to Cicero, and explains to the class: 'While I breathe, I hope. Both verbs are first-person singular present indicative. The phrase is elegant because spiro and spero are nearly identical in sound, which is a figure of speech called anaphora.'
The student's translation and grammatical identification are correct, but the rhetorical term is wrong. Which of the following correctly identifies the figure of speech AND explains why the student's chosen term is inapplicable?
- The figure is asyndeton, not anaphora; the omission of a conjunction such as et between spiro and spero is the defining rhetorical feature of the phrase, and the student should have focused on that structural absence rather than any incidental sound similarity.
- The figure is chiasmus, not anaphora; chiasmus involves an ABBA arrangement of parallel elements, and the near-identical sounds of spiro and spero at the ends of their respective clauses create precisely the crossing pattern that defines chiastic structure.
- The figure is paronomasia (punning on similar-sounding words), not anaphora; anaphora requires repetition of the same word or phrase at the beginning of successive clauses, which does not occur here since spiro and spero are different words in different positions. (correct answer)
- The student's identification is actually correct; in classical rhetoric anaphora encompasses any phonetic echo between adjacent words regardless of their position, so spiro and spero qualify and no revision is needed.
Explanation: When a question asks you to identify a rhetorical figure, always anchor your thinking in the precise definition of each term — classical rhetoric is exact, and swapping one figure for another is a common trap.
The student's error is confusing paronomasia with anaphora. Paronomasia is the deliberate use of words with similar sounds but different meanings to create a wordplay effect — exactly what spiro ("I breathe") and spero ("I hope") accomplish. The near-identical sounds create a witty, memorable pairing that links the act of breathing to the act of hoping. This makes C the correct answer. Crucially, C also explains why anaphora fails: anaphora requires the same word or phrase to be repeated at the beginning of successive clauses (think "We shall fight on the beaches, we shall fight on the landing grounds..."). Here, spiro and spero are different words and do not open parallel clauses in the same position.
A is wrong because asyndeton describes the omission of conjunctions in a list or series. While Dum spiro, spero does lack an explicit conjunction, that structural feature isn't what makes the phrase rhetorically celebrated — the sound-play is. B is wrong because chiasmus requires an ABBA reversal of grammatical or conceptual elements across clauses; nothing reverses here. D is simply false — anaphora has never been defined in classical rhetoric to cover any phonetic echo regardless of position.
Your study tip: memorize the "location rule" for anaphora — it's always about position (clause-opening repetition), never just about similar sounds. That distinction will protect you on any rhetorical identification question.
Question 3
A student encounters the phrase In medias res while reading about epic poetry conventions. She notes that the phrase comes from Horace's Ars Poetica and means 'into the middle of things.' Her classmate argues that medias must be nominative because it describes the subject of the implied verb 'to plunge.'
The classmate's grammatical reasoning is flawed. Which of the following most precisely explains why medias is accusative and what role it plays in the phrase?
- Medias is accusative because it functions as a predicate adjective after the implied copula esse, describing the state of the narrative action as being 'in the middle'; the preposition in is incidental and does not govern the case.
- In always takes the ablative in classical Latin prose, so medias is actually ablative plural feminine; the classmate is wrong that it is nominative, but the original student is also slightly wrong to call it accusative—the phrase means 'in the midst of things,' not 'into.'
- In followed by the accusative expresses motion toward or into something; medias res ('the middle things/affairs') is the accusative object of in, indicating the destination of the implied motion—'into the middle of things'—so medias is accusative plural feminine agreeing with res. (correct answer)
- Medias is accusative plural because res is a fourth-declension noun whose accusative plural is identical to its nominative plural, and Latin convention requires the modifier to take accusative when the head noun is ambiguous between nominative and accusative.
Explanation: Whenever you see a Latin prepositional phrase, your first move should be to identify which case the preposition governs — because in Latin, in does double duty depending on meaning. With the ablative, in means "in" or "on" (location). With the accusative, in means "into" or "toward" (motion). This distinction is the entire key to the phrase in medias res.
Here, in governs the accusative because the phrase conveys motion into something — specifically, plunging into the middle of a narrative already in progress. Res is a fourth-declension feminine noun, and medias is its accusative plural feminine modifier, agreeing perfectly in case, number, and gender. Together, medias res is the accusative object of in, and the full phrase means "into the middle of things." Answer C captures this precisely.
Answer A fails immediately because predicate adjectives follow a linking verb and take the nominative, not the accusative — and in is not "incidental" at all; it's the preposition governing the entire construction. Answer B makes a reasonable-sounding but false claim: in does NOT always take the ablative. It takes ablative for location and accusative for motion — this is one of the most tested preposition rules in Latin. Answer D invents a fictional rule. Latin does not require a modifier to take the accusative simply because a head noun is "ambiguous"; modifiers agree with their noun in whatever case the noun actually is.
Your study tip: memorize in as a dual-case preposition — ablative = location ("in the forum"), accusative = motion ("into the forum"). When you see in medias res, the accusative signals direction, not place.
Question 4
Students are practicing the motto Fortis Fortuna adiuvat ('Fortune favors the brave'). One student notes that Terence wrote Fortes fortuna adiuvat and asks whether changing fortis (nominative singular) to fortes (nominative plural) changes the fundamental meaning of the motto. Another student replies that the two forms are simply stylistic variants and are semantically equivalent.
Which of the following best evaluates whether Fortis (nominative singular) and Fortes (nominative plural) produce meaningfully different statements, and why?
- They are fully equivalent because Latin uses singular and plural adjectives interchangeably for gnomic statements, and since both forms share the identical nominative function as subject of adiuvat, no meaningful semantic distinction exists between them.
- They produce subtly different statements: fortis refers to a single brave person or 'the brave one' generically, while fortes refers to brave people collectively as a class; the core message is similar, but the plural form makes a broader, more universal claim. (correct answer)
- They are meaningfully different because fortis is also the genitive singular of fors ('chance'), shifting the translation to 'Fortune aids chance itself'; the singular therefore represents an entirely different grammatical construction rather than a mere stylistic variant of the plural.
- They produce meaningfully different statements because fortes is simultaneously the accusative plural, which would recast brave people as the object of adiuvat rather than the subject, fundamentally reversing who acts and who receives Fortune's favor.
Explanation: When analyzing how number (singular vs. plural) affects meaning in Latin gnomic statements — timeless truths meant to apply universally — you need to consider both grammar and semantics carefully.
The nominative singular fortis functions as a subject meaning "the brave person" or "a brave person," framing the motto as a generic claim about any individual who embodies bravery. The nominative plural fortes means "brave people" collectively, making the claim broader and more universal — Fortune favors brave people as a class. Both versions deliver essentially the same inspiring message, but fortes casts the net wider. This makes B the best answer: the forms are not purely identical in meaning, but the difference is subtle rather than fundamental.
A is tempting but overclaims. Latin can use singular adjectives generically, but that doesn't mean the forms are interchangeable without distinction — claiming they are "fully equivalent" ignores the real, if subtle, semantic difference between individual and collective reference.
C introduces a clever-sounding trap. While fortis can indeed be genitive singular of fors, context here makes the nominative reading overwhelmingly correct — fortis parallels fortes as subject of adiuvat, not a genitive modifier. Don't let alternate paradigm forms distract you from context.
D misapplies a real grammatical fact. Yes, fortes is also accusative plural — but so what? Word order and context (Fortune is adiuvat's subject here, not the object) rule out that reading. A form's possible case doesn't override what context demands.
Study tip: When a Latin form is ambiguous, always let context decide the case — and remember that subtle number differences in gnomic expressions matter semantically, even when the core message survives both ways.
Question 5
In a Latin study group, students are asked to explain the phrase Cogito, ergo sum (Descartes) in terms of its Latin grammar. One student says: 'All three words are first-person singular present indicative. Cogito means I think, ergo is a conjunction meaning therefore, and sum means I am.' A second student challenges: 'Ergo is actually an adverb, not a conjunction, in classical Latin usage.'
The second student raises a fine grammatical point. Which of the following best resolves the debate about ergo and also identifies any additional grammatical issue with the first student's analysis?
- The first student is correct: Descartes wrote in early modern Latin, where ergo had evolved into a coordinating conjunction like igitur, making both words effectively interchangeable; the classical adverb-versus-conjunction distinction therefore does not apply to this philosophical text.
- The second student is largely correct: ergo functions as a conjunctive adverb (or adverb of inference) in classical Latin rather than a coordinating conjunction; the first student's analysis of the verbs is accurate, but calling ergo simply a 'conjunction' conflates two distinct grammatical categories. (correct answer)
- Both students are wrong: ergo is a preposition governing the genitive in classical Latin (meaning 'on account of'), so the phrase translates as 'I think, therefore of being,' with sum functioning as a gerund in the genitive rather than as a finite verb.
- The second student is correct about ergo, but the first student's verb analysis also contains an error: sum is not present indicative but a subjunctive form expressing contingency, which is why Descartes uses it to convey the uncertain rather than definitive nature of existence.
Explanation: When analyzing Latin grammar, it helps to distinguish between parts of speech that look similar in translation but behave differently structurally. This question tests whether you understand the classical classification of ergo and whether the verb analysis in the passage holds up.
In classical Latin, ergo is best classified as a conjunctive adverb (or adverb of inference) — it modifies the logical relationship between clauses rather than joining them as a true coordinating conjunction (like et, sed, or igitur in some usages). The second student is right to flag this. Meanwhile, cogito and sum are both unambiguously first-person singular present indicative active — cogito from cogitare and sum from esse. So the first student's verb analysis is sound; only the label "conjunction" for ergo is imprecise. This makes B the best answer: it validates the second student's correction while confirming the verbs are correctly identified.
A is wrong because it dismisses the distinction entirely by claiming early modern Latin erased it — an overclaim with no classical grammatical basis, and the question specifically asks about classical usage. C is factually creative but incorrect: while ergo can function as a preposition meaning "on account of" governing the genitive in archaic Latin, this reading makes no sense applied to Cogito, ergo sum, and sum is clearly a finite verb, not a gerund. D fabricates an error in the verb analysis — sum is straightforwardly present indicative, not subjunctive; the subjunctive of esse would be sim.
As a study tip: watch for questions that mix a valid point with a subtle overcorrection. The correct answer here agrees with the challenger but stops short of inventing new errors.
Question 6
A student is asked to explain the motto Ars longa, vita brevis (from Hippocrates, rendered into Latin by Seneca) in class. She translates it as 'Art is long, life is short' and adds: 'The verb est is omitted twice in this phrase, which is an example of ellipsis. Both longa and brevis are predicate nominatives.'
A classmate challenges her, saying that longa and brevis must be in the nominative because they modify the nouns ars and vita, making them attributive adjectives, not predicate nominatives. Which response best adjudicates this disagreement?
- The original student is correct: longa and brevis are predicate nominatives completing an implied copula; attributive adjectives modify a noun within a phrase without requiring a verb, but here the copulative meaning ('is long,' 'is short') is clearly intended, and ellipsis of est is standard in Latin proverbs. (correct answer)
- The classmate is correct: because Latin attributive and predicate adjectives are identical in form, the default interpretation when no verb is present is attributive; predicate nominatives are only valid when an overt copula appears in the text, which it does not here.
- Both are wrong: longa and brevis are in the ablative case, forming an ablative of description, so the phrase means 'art of long duration, life of short duration'; the omission of est is a separate stylistic feature unrelated to the case of the adjectives.
- Both are partially right: the adjectives are nominative, as the classmate notes, but they function as secondary predicates rather than either attributive modifiers or copular complements, a construction that requires no est and is distinct from standard predicate nominative usage.
Explanation: When you encounter a question about Latin adjective function, the key distinction to master is attributive vs. predicate adjectives. An attributive adjective modifies a noun directly within a noun phrase (longa vita = "the long life"), while a predicate adjective completes a copula — expressed or implied — to make a statement about the subject (vita longa est = "life is long"). Crucially, both constructions are identical in form in Latin; context and sentence structure determine which function is at play.
Answer A is correct because Ars longa, vita brevis consists of two independent clauses, each making a full predication. The ellipsis of est — extremely common in Latin proverbs, maxims, and sententiae — signals that longa and brevis are completing an implied copula, making them predicate nominatives. The copulative meaning "art is long, life is short" is grammatically and contextually unambiguous.
Answer B is wrong because it invents a rule that doesn't exist: Latin does not default to attributive interpretation when no overt verb appears. Ellipsis of est is a well-documented, standard feature of Latin, especially in proverbial expressions, and predicate nominatives with implied copulas are entirely valid.
Answer C is wrong on basic morphology: longa and brevis are first/second declension nominative forms, not ablative. An ablative of description would require the genitive or ablative (vitae brevis or vita brevi), neither of which appears here.
Answer D is wrong because "secondary predicate" is a real but distinct construction (typically involving a noun or adjective in an accusative-plus-infinitive or participial structure) — it doesn't apply here and misrepresents standard Latin grammar.
Study tip: Whenever you see a Latin phrase with adjectives but no explicit verb, ask whether the sentence is making a predication (predicate adjective + ellipsis) or simply describing a noun (attributive). Proverbs almost always use predicate ellipsis — memorize a few classic examples like Ars longa, vita brevis to anchor that pattern.
Question 7
Two students are practicing the phrase Carpe diem from Horace's Odes (I.11). One student says it means 'seize the day' and comes from the verb carpo. The other says the full line ends with quam minimum credula postero, which she translates as 'trusting as little as possible in tomorrow.'
The second student's translation of quam minimum credula postero is debated. Which analysis of the phrase's grammar is most accurate?
- Postero is a genitive singular modifying diem (implied from carpe diem earlier in the poem), so the phrase means 'trusting the day of tomorrow as little as possible,' and credula is accusative agreeing with diem rather than nominative.
- Quam minimum intensifies a comparative adjective, so credula must be in the comparative degree (credulior) for the construction to be grammatical; the translation 'as little as possible' is therefore only valid if we emend the text to read credulior.
- Credula is an ablative absolute construction with postero, together meaning 'tomorrow having been trusted,' which is an idiomatic way of expressing regret about past reliance on the future rather than a command to distrust it.
- Quam minimum is a superlative construction meaning 'as little as possible'; credula is a nominative feminine adjective agreeing with an implied subject (Leuconoë, addressed in the poem); and postero is dative singular ('in/to tomorrow'), giving 'trusting as little as possible in tomorrow.' (correct answer)
Explanation: When analyzing a Latin phrase like quam minimum credula postero, your first move should be to identify each word's form and ask: what does each word modify, and what construction is at work?
The phrase comes from Horace addressing Leuconoë, a woman, directly throughout the poem. That context is your anchor. Quam minimum is a standard Latin superlative idiom meaning "as little as possible" — quam paired with a superlative adverb intensifies it to the maximum degree. Credula ("trusting, credulous") is a nominative feminine singular adjective, which logically agrees with Leuconoë as the implied subject being addressed. Postero ("tomorrow, the future") is dative singular, because credulus takes the dative for the thing trusted. Put it together and you get D: "trusting as little as possible in tomorrow" — a command to live in the present rather than betting on the future.
Choice A falls apart because postero cannot be genitive here — its form is dative, not genitive — and credula is clearly nominative, not accusative. Choice B misunderstands the quam minimum construction entirely: it does not require a comparative adjective (credulior). Quam + superlative adverb modifies the degree of the quality, not the adjective's degree of comparison, so credula in the positive is perfectly grammatical. Choice C invents an ablative absolute that doesn't exist — ablative absolutes require a noun and participle (or noun + noun) in the ablative, and neither credula nor postero is ablative here.
Your takeaway: memorize that quam + superlative = "as [adjective/adverb] as possible," and always check the dative of adjectives like credulus that govern a complement noun.
Question 8
During a seminar on institutional mottos, students are asked to compare E pluribus unum with Ex uno plura. The instructor notes that one phrase is the traditional motto of the United States and the other is a modern inversion, and asks students to identify which is which and explain the grammatical difference between the two.
A student claims that E pluribus unum and Ex uno plura use identical prepositional constructions and therefore mean the same thing in opposite directions. Which response most accurately evaluates this claim?
- The claim is partly correct: both use ex/e with the ablative to indicate origin, but the meanings are directionally opposite—'one out of many' versus 'many out of one'—so the constructions are parallel but the phrases do not mean the same thing. (correct answer)
- The claim is fully correct because e and ex are interchangeable variants of the same preposition, both ablatives indicate the same source relationship, and reversing unum and plura simply inverts identical grammar to produce identical semantic content.
- The claim is incorrect because e governs the ablative while ex governs the genitive, making the two phrases grammatically distinct constructions that cannot be considered parallel inversions of each other.
- The claim is incorrect because plura in Ex uno plura is a nominative subject requiring a verb, whereas unum in E pluribus unum is an accusative predicate, so the two phrases use fundamentally different case functions and cannot be structurally compared.
Explanation: When comparing Latin prepositional phrases, you need to evaluate two separate questions: are the grammatical constructions parallel, and do parallel constructions necessarily produce identical meanings? This question tests both at once.
Both E pluribus unum and Ex uno plura use the same preposition — e and ex are simply phonological variants of one word, with ex appearing before vowels and sometimes consonants, and e appearing before consonants. Both forms govern the ablative case. In the first phrase, pluribus is ablative plural of multus/plus (many), and unum is nominative/accusative singular (one). In the second, uno is ablative singular and plura is nominative/accusative plural. So yes, both use ex/e + ablative to express origin or source — a structurally parallel construction. However, swapping the ablative and nominative terms reverses the direction of meaning entirely: "one from many" becomes "many from one." Same grammar, opposite sense. That makes A correct.
B is wrong because it conflates grammatical parallelism with semantic identity. Parallel structure does not mean identical meaning — direction matters enormously.
C is factually wrong about Latin grammar. Ex and e are the same preposition and both govern the ablative, never the genitive. This is a made-up distinction.
D is wrong because it invents a case conflict that doesn't exist. Both unum and plura function the same way in their respective phrases — as the resultant nominative/accusative — so there is no fundamental case mismatch between the constructions.
Study tip: Always separate structure from meaning in Latin analysis — two phrases can be grammatically parallel while being semantically opposite. Don't let symmetry of form imply equivalence of content.
Question 9
Students in a Latin-2 seminar are asked to explain the phrase Veni, vidi, vici (Caesar) and discuss its rhetorical effect. One student says: 'All three verbs are perfect indicative active, first-person singular. The phrase demonstrates tricolon crescens because each verb has more syllables than the last.' Another student disagrees: 'It's actually tricolon but not crescens—each verb has the same number of syllables.'
Setting aside rhetorical labels, which student has correctly analyzed the syllable counts of veni, vidi, and vici, and what does this imply about the rhetorical classification?
- The second student is correct: each verb has exactly two syllables (ve-ni, vi-di, vi-ci), so the phrase cannot be tricolon crescens, which requires increasing length; it is a tricolon better characterized by homoioteleuton (similar endings) and asyndeton (no conjunctions). (correct answer)
- The first student is correct: veni has two syllables, vidi has two, but vici has three (vi-ci-i) because the long final vowel counts as an additional mora that creates a third syllable, so the series does grow in length and qualifies as tricolon crescens.
- The first student is correct because tricolon crescens measures syntactic weight and semantic escalation rather than raw syllable count; even with all three verbs at two syllables, the mounting narrative force—arriving, seeing, conquering—makes the figure crescens by classical definition.
- Both students are wrong: veni has three syllables (ve-e-ni) because its long ē functions as a separate vowel, making the first verb longer than the others and reversing the pattern into tricolon decrescens, which is the rhetorical effect Caesar actually intended.
Explanation: When analyzing rhetorical figures in Latin, you need two skills working together: accurate phonological analysis (how words actually break into syllables) and precise knowledge of rhetorical terminology. This question tests both simultaneously.
Latin syllabification follows a clear rule: each syllable contains exactly one vowel sound (diphthongs count as one). Applying this to Caesar's phrase, ve-ni = 2 syllables, vi-di = 2 syllables, vi-ci = 2 syllables. All three verbs are perfectly equal in length. The second student's syllable count is right, and A is the correct answer. Because all three members are equal in length, the phrase cannot be tricolon crescens, which by definition requires each successive element to be longer or weightier than the previous one. Instead, the figure is a plain tricolon—three parallel members—enhanced by homoioteleuton (the identical -i endings) and asyndeton (no conjunctions linking the verbs).
Choice B invents a false rule. Long vowels in Latin create mora (duration) but do NOT split into separate syllables. A long vowel is still one vowel, one syllable nucleus—so vici remains two syllables, not three.
Choice C smuggles a real observation (semantic escalation from arriving → seeing → conquering) into a false definitional claim. Classical tricolon crescens is measured by formal length or syntactic weight, not narrative drama alone. The semantic escalation is real, but it doesn't make the figure crescens by classical definition.
Choice D fabricates syllabification entirely. A long ē in vēni is one vowel sound, not two. Latin does not split long vowels into separate syllables.
Study tip: Always syllabify Latin words before applying rhetorical labels—phonology grounds everything else.
Question 10
A law student encounters the phrase Ignorantia legis neminem excusat on the wall of a courthouse. She tells her study partner that it means 'Ignorance of the law excuses no one' and that the phrase contains a gerund in the genitive case modifying legis.
The student's translation is correct, but her grammatical analysis contains an error. Which of the following correctly identifies the error and explains the actual function of legis in the phrase?
- Legis is a dative singular form indicating the indirect object ('for the law'), making the student's case identification doubly wrong; additionally, her claim of a gerund fails because Latin gerunds cannot take a noun in direct apposition the way legis appears here.
- Legis is genitive singular, but the student is also correct that a gerund is present: ignorantia is the gerund of ignoro in the nominative case, which is precisely why it can function as the grammatical subject of excusat.
- The student is right that legis is genitive, but the actual gerund in the phrase is excusat, which is a gerundive form agreeing with neminem in the accusative and expressing obligation rather than a simple finite verb.
- Legis is a genitive singular noun ('of the law'), not a gerund; no gerund appears in this phrase—ignorantia is an abstract first-declension noun in the nominative functioning as the subject of excusat. (correct answer)
Explanation: When analyzing Latin phrases, you need to distinguish carefully between word forms and word types — specifically, knowing the difference between a gerund and a regular noun is essential here.
Ignorantia legis neminem excusat breaks down cleanly: ignorantia is a first-declension abstract noun (nominative singular, subject), legis is a second-declension noun lex in the genitive singular meaning "of the law," neminem is the accusative object of excusat, and excusat is a third-person singular present indicative verb. The translation "Ignorance of the law excuses no one" is perfectly accurate. The student's error is claiming legis is a gerund — it isn't. There is no gerund anywhere in this phrase. D is correct.
A is wrong on two counts: legis is clearly genitive, not dative, and the invented grammatical rule about gerunds and apposition is fabricated nonsense designed to sound authoritative.
B contains the most tempting trap. Yes, legis is genitive — but ignorantia is absolutely not a gerund. A gerund of ignoro would be ignorando (various cases of the verbal noun), never ignorantia, which is simply a standard noun derived from the adjective ignorans. Gerunds also cannot appear in the nominative case in classical Latin.
C invents a problem with excusat, which is straightforwardly a finite verb, not a gerundive. A gerundive would agree with a noun and carry obligation (excusandus/a/um).
Your study tip: memorize that Latin gerunds decline like second-declension neuter nouns (amandum, amandi, amando) — if a word doesn't fit that pattern, it isn't a gerund.