The correct answers are A) Russia and D) China.
The nations that experienced major Revolutions in the 20th century were Russia and China.
Russian Revolution of 1917 transformed the political and social life of Russia. Lenin, as the leader of the Communist Party, overthrew the Russian Tsar and implemented Communism in the nation. In China, the Civil War was won by the Communist Party lead by Mao Zedong in October 1949. The Communist army defeated the army of the Nationalist Party, and Zedong officially installed Communism in the People´s Republic of China.
