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.
"He plans to become a test pilot for experimental aircraft."
The answer is option A.
A) the world is in need of a good cleansing.
The answer is: 3. Johnson defends the right of all people to vote and believes the existing laws are not clear enough for voters to understand them.
President Lyndon B. Johnson addressed to the congress a meeting to discuss the voting right, claiming for equal voting rights, he uses the fifteenth amendment, where after the civil war the right to vote was gave to all the citizens regardless the race or skin color.