Self-study
Art critic: Support Abstract paintings are nonrepresentational, and so the only measure of their worth is their interplay of color, texture, and form. ███ ███ █ ████████ ██ ████ ███ ██████ ██ █████████ ███████ █████████ ██ ██████ █████████ ████ ██ ███ ████ ████████████ ███ ████ ███████ ██████████████ ██ █████ ██████████ ████████ ████████ ███ █████ ██ █ ███████████ ███████████ ███ █████
Summary
The art critic concludes that abstract painting can never be a politically significant art form. Why? Because, for a painting to inspire political action, it must clearly represent scenes of injustice. And abstract painting is nonrepresentational. 
Notable Assumptions
The conclusion is about being politically significant, but the support is about inspiring political action. We don’t know that those are identical. Therefore, the author must be assuming that, if a painting can’t inspire political action, it isn’t politically significant art. (The contrapositive: being politically significant requires inspiring political action.) Note that this assumption is both necessary and sufficient to prove the argument’s conclusion.
17.
Which one of the following ██ ██ ██████████ ████ ██ ████████ ██ ███ ███ ████████ █████████
a
Abstract painting cannot █████████ ██████ ██ ████
The art critic has no need to make such a broad assumption. He could believe that abstract painting inspires people to non-political action.
b
Unless people view ███████████████ ██ ██████ ██████████ █████ █████████ ████████ ██ ██████████████
The significance mentioned in the stimulus is that of art, not of people’s political activity. The significance of people’s political activity is irrelevant to the art critic’s argument.
c
Only art that ███████ ██████ ██ ███████ ██████ █████████ ██ ███████████ ████
The art critic’s conclusion is that abstract art lacks political significance, not that it lacks any form of significance. He could believe that abstract art is significant, but only for non-political reasons.
d
Paintings that fail ██ ████ █ ██████ ██ █████████ ██████ ██████ ██ ███████████ ████████████
The negation would be: Even if a painting fails to move a viewer to political action, it can still be politically significant. This renders the argument’s support—that abstract art fails to move a view to political action—irrelevant to its conclusion. Therefore, the author must assume (D) is the case.
e
The interplay of ██████ ████████ ███ ████ ██ ███ █ ███████ ██ ███ █████ ██ ████████████████ ██████████
The art critic’s argument is about abstract paintings; consequently, he doesn’t need to make any assumptions about representational paintings.