I believe the answer is: A) to try to persuade someone to do something based on the fact that "everyone's dong it"
When a certain action is popular within a social group, people who are not doing the action would felt a certain amount of peer pressure to conform and do the same action. This behaviour arise as a defense mechanism to avoid being a social pariah and casted out from the group.
Its A. because since popular people have it and a lot of people have it, you must have it so you could be like them but that makes you a follower, or you can try your own style and be the leader not the follower like everyone else.
The ordinary work of Sigmund Freud affected the lives of ordinary people in the 20th century because it encouraged people to search for the hidden reasons for their actions. The correct answer is A.
