why is it not C?

@Jessica-Killeen, Happy to help! You're asking why the answer isn't (C). Let's first take a look at the stimulus. We're told that the government wants to encourage works of artistic excellence by having a funding program. Senator Beton, however, argues that this is not possible because artists will inevitably try to please those who provide them with funding. Therefore, he concludes that government funding can't lead to the creation of works of true artistic excellence. In the stimulus, Senator Beton's primary support for her argument is that a government-funded artwork can never reflect the independent artistic conscience of the artist. The problem with the rest of her argument is that she never states why it's imperative that the art reflects the artistic conscience of the artist. Thus, in doing so, Senator Beton assumes that if art is to be excellent, it must reflect the artistic conscience of the artist. The question stem reads, "Which one of the following is an assumption on which Senator Beton’s argument is based?" Based on the stem, we know this is a strengthen with a necessary premise question. Through our analysis of the stimulus, we've already identified the big assumption Senator Beton is making, so let's look for an answer choice that matches our prediction. We can use the negation test to verify the correct answer. Since the question is asking us for a necessary premise, we can negate answer choices to see if the negation would make the argument fall apart. If the negation does make the argument fall apart, then we know the original form of the answer choice was necessary for the argument, so it must be a necessary premise. You asked about (C). (C) says, "Distribution of government funds for the arts is based on a broad agreement as to what constitutes artistic excellence." The negation of (C) would say, "Distribution of government funds for the arts is not necessarily based on a broad agreement as to what constitutes artistic excellence." The problem with (C) is that Senator Beton's argument does not assume anything about how the distribution of government funds for the arts is distributed. Since her argument isn't assuming anything about this, this cannot be an assumption that her argument depends on, so we can safely eliminate (C). The negation of (C) doesn't wreck Senator Beton's argument. (E) says, "A contemporary work of art that does not reflect the independent artistic conscience of the artist cannot be a work of true artistic excellence." The negation of (E) is, "A contemporary work of art that does not reflect the independent artistic conscience of the artist can be a work of true artistic excellence." This sounds just like what we anticipated during our analysis of the stimulus. To verify, let's see if the negation would wreck the argument. If the negation were true, the argument would fall apart because Senator Beton is hinging on the fact that in order for a work to possess true artistic excellence, the work must reflect the independent artistic conscience of the artist. (E)'s negation is saying that these two ideas (a contemporary work of art that doesn't reflect the independent artist conscience of the artist AND the work beign one of true artistic excellence) are actually compatible with each other. If this were true, Senator Beton's argument would fall flat. Thus (E) is a necessary premise and is our answer choice. Does this help? Let us know if you have any more questions!