What is the professor's opinion about the relationship between English landscape painters and Loutherbourg? A. He thinks English landscape painters were unfair in their criticism of Loutherbourg's work. B. He thinks Loutherbourg's relationship with English landscape painters was less important than most experts think. C. He thinks Loutherbourg and the English landscape painters probably influenced each other. D. He thinks English landscape painters helped Loutherbourg's work gain in popularity.