Question

How did the alliance system in Europe most likely contribute to the start of World War I?

The countries in the alliances sought protection against enemies by sharing military personnel.
The countries in the alliances agreed to work together to gain power through colonization.
The countries in the alliances agreed to share economic resources based on open trade markets.
The countries in the alliances signed treaties agreeing to defend each other in times of war.

Answer 1

The correct answer is: The countries in the alliances signed treaties agreeing to defend each other in times of war.

Explanation: Mutual defense agreements meant a conflict between two countries (e.g., Austria-Hungary and Serbia) quickly drew in their allies (Russia, Germany, France, Britain), turning a regional incident into a wider war.