The conclusion of the paragraph is that self-help books make readers more anxious and depressed and hence, they have the opposite effect on a person.
A – Wrong
The focus of the paragraph is the effectiveness of self-help books. This statement does not provide a flaw in the conclusion.
B – Correct.
Self-help books are made for anxious and depressed people. Hence, these are the people that would be most benefited from such books.
C – Wrong
This statement is already considered in the text. The last sentence says that those who read such books are more likely to become anxious and depressed when compared to people who have never read them. This means there could be some people who are depressed and anxious even though they have never read self-hep books.
D – Wrong
Although this statement may be true, it is not a flaw in this case. The text discusses the connection between anxiety and self-help books but does not mention anything about a lack of this connection.