I believe you have a typo when it comes to the first option - it should be athletics, not athletic. The word athletic is an adjective, and the word athletics is a noun.
That being said, the correct answer is A. athletics. Even though this noun ends in -s, it is still singular. The rest of the options are all plural nouns.
Ad hominem means the man so it probably means one persons opinion and ad populem means the population so maybe the general
populations opinion
It can affect your life in the business world in a lot of ways. If you have good rhetoric, you're more likely to be hired and you'll probably perform better since you'd be more persuasive and eloquent.
If you have poor rhetoric, you're probably less likely to be hired because you don't know the vocabulary or you're not very persuasive. You also might perform poorly (for instance if you had to sell something and you didn't have good speech)
Answer:
A. introducing the main char
