(B) vs. (C)

@Julie-V, Let's look at (B) and (C). (B) says, "citing evidence that requires a reevaluation of a conventionally held view" The passage does not state that Brown's view is a conventionally held view. Additionally, the author is not asking for a mere reevaluation, she is showing that other causes could have factored into Venetian painting styles, so we can get rid of (B). (C) says, "discussing factors that explain a difference in painting styles" The author is attempting to argue that various factors affected the difference between Tuscan and Venetian painting styles; this is the primary purpose of the passage. Thus, (C) is the correct answer choice. Does this answer your question? Let us know if you'd like further clarification!

It does answer my question, thank you!