Answer: B. The founding of the Communist Party in China
Explanation: The Communist Party of China which was initially a study society and informal network was founded by Chen Duxiu and Li Dazhao in Shanghai in 1921. Informal meetings had been held both in China as well as overseas. The official beginning of the Communist Party of China began with the 1st Congress held in Shanghai and Jiaxing in July 1921 which was composed of 13 men.
The birth of the party, with about 60members, was declared while at a meeting held on a boat on South Lake. The formal and unified name "Chinese Communist Party" was adopted and the final agenda was carried out. By 1945, the party had over 1.2 million members.