Which of the following is correct about American NATURALISM?
A. Naturalism, like realism, had come from Europe.
B. Naturalism had been shaped by the war, by the social upheavals and the disturbing teachings of Charles Darwin.
C. American Naturalists attempt to achieve extreme objectivity and frankness, presenting characters of low and social and economic classes who were dominated by their environment and heredity.
D. All of the above.