You might be tempted to see the word “arbiter” in “arbitrary.” They are not unrelated, for both pertain to a judgment being made. However, when something is "arbitrary," it is done at the whim of the one judging. It has no real reason other than that person’s desires or passions. Therefore, an “arbitrary” decision could be called “whimsical.” All of the other answers (except “flimsy”) are meant to trick you.

When someone is "diligent," he or she is devoted to his or her work. Now, while this would likely make you think that "devoted" would be the best option, actually "industrious" is slightly better. When someone is "industrious," he or she is works with great care and devotion. This expresses the role of work in the devotion better than the simple word "devoted."

When someone is "precise," he or she is exact about details. Now, this can be used to mean that the person is not vague (in speech, writing, etc). It can also mean that the person is very exacting about details when working. Such a person is well described as being "methodical." This word describes someone who works on something by using a fixed method. This allows him or her to address all needed details for the given matter (instead of randomly working on it and, thus, missing important details).

“Lax” means negligent, not giving enough attention to something, or not taking something seriously enough, so "negligent" is the best synonym amongst the answer choices. As for the other answer choices, “odious” means unpleasant, revolting, or disgusting; “prolific” means able to produce a large quantity of something quickly; “tedious” means dull and boring; and “remorseless” means not feeling guilty about one's actions.

Someone who is "affable" is easy to talk with and pleasant to be around. "Genial" best conveys this sense (a likable pageant contestant might be named "Miss Congeniality"—a related word).

“Jovial” means jolly, friendly and "cheerful." As for the other answer choices, “uncomfortable” means slightly painful or just removing or lacking all comfort; “hollow” means containing empty space on the inside; "nuanced" means full of subtle details; and “deft” means skillful.

“Bleak” means desolate, bare, lifeless, and depressing. A situation can also be “bleak,” which means hopeless. As for the other answer choices, “fertile" can mean able to produce lots of vegetation and crops; "abundant" means found in large numbers; “perceptive” means insightful, sensitive, and noticing many things; and "flagrant" means overt and brazen and is often used to describe instances in which someone purposely breaks rules.

The word “myriad” is derived from the Greek for "10,000." In general, it is used to describe a countless multitude of things. For that reason, the best option among the provided answers is “innumerable.” An example usage would be, “Roger wished to do something so foolish that his friends were able to provide him with myriad reasons, overwhelming him with reasons for making such a stupid choice.”

"Forlorn" means miserable or sad. "Ecstatic" is the antonym; it means extremely happy. "Arrogant" means conceited or full of oneself. "Informed" means having knowledge or information regarding a topic. "Significant" means important or noteworthy.

"Intractable" means difficult or burdensome; therefore, "unmanageable" is the best answer.