Cant answer without the question
It was signed on June 28, 1919, by the Allied and associated powers and by Germany in the Hall of Mirrors in the Palace of Versailles and went into effect on January 10, 1920.
Answer:
You didn't include the answers...
There are four If you remember the old acronym MAIN.
M-Militarism
A-Aliances
I-Imerialism
N-Nationalism