The suspect is accused of plotting a serious crime. The answer, what was discovered, will indicate the level of deception involved in the crime. "Subterfuge," meaning a trick or deception, is the correct answer.

The Duke continues to look down on "lower classes," which is contrasted with the correct answer. The best choice will then mean a belief in equality, which is the definition of "egalitarianism."

The phrase "conducting wine tastings so long," indicates he considered himself some kind of expert, and the correct answer should reflect that. "Connoisseur," meaning someone with refined taste and judgement, is the best fit in the sentence.

The best clue words in this example are "grammarian" and "linguistic history." The latter makes "histories" unlikely, if only because of the repetition that this would impose. It is perhaps tempting to use "meanings," as a grammarian would pay heed to meanings in explication—just as he would pay heed to the declensions and inflections of words;  however, if we are considering linguistic history (even if flawed), we are above all concerned with etymology, which studies (or at least purports to study) the history of words and the meanings that can be gleaned from such history.

The key word is in the second sentence is "err." It might be tempting for that reason to consider "error" or "mistake," but we are provided a specific type of error, namely a grammatical one: "solecism" matches the intended meaning most closely.

The first sentence leaves our meaning so general that any of the terms might fit (though the case for "gusto" is particularly weak). The second sentence gives us a much better limiting factor, namely, the beauty of his form as a swordsman. In this case, we are more concerned with form than brute strength or anything similar; therefore, while perhaps "celerity" or "ability" might distantly apply, "finesse" captures the ballet-like beauty most directly.

The man's paranoia about fires means he would find a way to deal with a fire everywhere.  The correct answer will describe a method to handle a fire. "Egress," meaning an exit, is the correct answer choice.

The sentence outright states the media outlets were "reporting the same story."  The correct answer will indicate the media was telling the same story.  "Consensus," meaning a general or widespread agreement, is the best fit.

The trash had essentially found a permanent home in the man's backseat, and the correct answer will indicate that. "Receptacle," meaning container or vessel, is the best answer choice.

The sentence itself says the award winner had a "fight for voting rights." A "suffragist" is someone who fights for the right to vote, and it is the correct answer.