After Their Alliance Between Them Collapsed, How Did the Communists

After their alliance between them collapsed, how did the Communists avoid the suppression of the Nationalists?

A) They allied themselves with the invading Japanese Army.
B) They undertook a 6000-mile march to a remote area of the country.
C) They initiated a guerrilla war against the Nationalists.
D) They escaped to Taiwan and established an alternative government.
E) They disbanded and faded into the population.