China became a communist nation in 1949 with the proclamation of the People's Republic of China by Mao Zedong, following a civil war against the Nationalist government. This marked a significant shift in the country's political and social landscape. Therefore, the correct answer is C. 1949.
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China officially became a communist nation in 1949 when the People's Republic of China was established. This followed a civil war between the Communist Party and the Nationalist government. Mao Zedong's leadership marked the beginning of numerous social and economic reforms in the country. ;