The passage most strongly supports which one of the following inferences about Porter's own paintings? A. They often contained figures or images derived from the work of African artisans. B. They fueled his interest in pursuing a career in art history. C. They were used in Porter's book to show the extent of African influence on African-American art. D. They were a deliberate attempt to prove his theories about art history. E. They were done after all of his academic work had been completed.