Help with SAT sentence completion question?

Question

Question: For some time now, ----- has been presumed not to exist :the cynical conviction that everybody has an angle is considered wisdom.

A. rationality

B. flexibility

C. diffidence

D. disinterestedness (correct answer)

E. insincerity

Can someone explain why D is right? And also explain what the question is talking about?

Answer 1

The quoted sentence is saying that everyone is usually thought to be motivated by self-interest. 'Disinterestedness' means even-handedness, impartiality, lack of bias, lack of self-interest.  Hence disinterestedness has been presumed not to exist.

EDIT - I think french7suzi is right up to a point, but I would say that 'angle' means more than just 'opinion' here. There is nothing wrong with having an opinion, so it would not be 'cynical' to think that everybody has one. (Nor is there anything wrong with 'caring', provided it is unselfish.)  I think 'angle' rather means 'bias' or 'self-interest'.

Answer 2

Wow, you have to break that one down. Let's just take the end. "Everyone having an angle is considered wisdom" means "everyone has an opinion" "considered wisdom" could mean "considered the best way to think or believe." Ok, working back..."cynical conviction" means pessimistic way of thinking. "Has been presumed...." means "was thought imaginary."

"In the past up until now, .... was thought imaginary. The negative assumption that everyone on earth has an opinion (I think this is easier to understand if you remember "has an opinion" sometimes means the same thing as "caring") is the best way to think.

So what we are looking for is a word that describes someone who has no opinion. And that would be "disinterested" or soemthing similar.