Why is C the correct answer?

@mfujii, Happy to help. Let's look at (C). (C) says, "Although the creation of the early material of the Teatro Campesino was a collective accomplishment, Luis Valdez’s efforts and expertise were essential factors in determining the form it took." In this passage, the authors' main point comes at the end of the last paragraph of the passage. The author's conclusion is that Valdez did not create actos or Teatro Campesino on his even, but he did have a major role in their creations. (C) provides us a with a great paraphrasing of this, so it's the correct answer choice. The first sentence of the third paragraph does not contradict (C) because the author is just saying that these criticisms are sound for attacking the assertion that Valdez was individually responsible for the creation of actos. Being individually responsible for the creation of actos and being an essential part of the creation of actos are two separate things, and the author certainly thinks that Valdez was a very impotant player in their creation, albeit NOT the only player. Does this make sense? Let us know if you have any more questions!

Yes this makes sense! Also I realize now the first sentence of the third paragraph supports the author's point but is ultimately not the author's point but someone else's and the last sentence you pointed out gives the author's perspective on the issue. Thank you!

@mfujiii, you're welcome, and I'm happy to hear it helped!