For His Huge Murals of Mexican Political History,Diego Rivera __________

For his huge murals of Mexican political history,Diego Rivera __________.

A) designed the entire scene then had his assistants actually do the painting
B) did the mural during the summer, so the working surface would be dry
C) worked in short bursts of activity, for only one to two hours a day
D) sketched directly onto the wall with red chalk or charcoal