I would say that the best answer is A. C is definitely not the answer because of course, there is a relationship between art and literature.
Studying literature involves reading, thinking, interpreting, discussing, and writing. Studying art is analyzing and critiquing the artwork, as well as learning about the history of art. Putting both literature and art together creates a better understanding of the artwork and a more in-depth discussion about the artwork itself.
(I apologize for the late reply. Hopefully this answer is helpful to you though.)
Answer: B. He values artistic success over financial success for himself.
Based on Harburg's view of the Great Depression presented through the excerpt above, it can be deduced that he was never interested in financial success. He believes that artistic success is better than financial.