The correct timeline that accurately identifies the cause of aggression and conflicts that led to the Nanjing Massacre in China and contributed to the beginnings of World War II is:
Date: Aggression and Conflicts
- 1850s: Japan uses gunboat diplomacy to force trade with the Chinese.
- 1931: Japan seizes Manchuria from China.
- 1937: Japan invades the mainland of China, leading to the Nanjing Massacre.
This timeline illustrates Japan's aggressive expansion in China, starting with trade-related conflicts and culminating in military invasions, which were significant precursors to the broader conflict of World War II.