The most accurate response is: Nationalism united the rural people in China to stand behind communism as a form of government.
This reflects how the Chinese Communist Party (CCP) was able to leverage nationalist sentiments to gain support among the peasant population, which was crucial in their struggle against both foreign imperialism and the ruling Nationalist government. Nationalism played a significant role in mobilizing various segments of the population around the idea of a unified, independent China, which the CCP promised to deliver through their communist ideology.