Which of the following is listed in chronological order?
A. US enters WWI, Treaty of Versailles, Lusitania sunk, Zimmerman Telegram
B. Treaty of Versailles, Zimmermann Telegram, US enters WWI, Lusitania sunk
C. Zimmermann Telegram, US enters WWI, Treaty of Versailles, Lusitania sunk
D. Lusitania sunk, Zimmermann Telegram, US enters WWI, Treaty of Versailles