C) Chiang Kai-shek
At the age of 31, the soldier Chiang Kai-shek joined the Kuomintang Party (KMT) in 1918, which had been founded by Sun Yat-sen. After Sun's death in 1925, he became his successor. As leader of the party, Chiang expelled the communists (who were admitted to the party before), led a military campaign against local warlords in northern China and gained the victory, which contributed to China's unification, among other accomplishments.