Question

introduction to world war i
underlying causes
what was the purpose of forming alliances
in world war i?
several factors combined to create a tense and
explosive environment in europe in the early 20th
century, ultimately leading to world war i.
eliminating trade barriers and adding new markets
for products
dominating other countries and expanding
territories
providing protection and support among member
nations

Explanation:

In World War I, alliances like the Triple Entente and Triple Alliance were formed to provide mutual protection and support. Eliminating trade barriers was not the main purpose of WWI alliances, and dominating/expanding was more about imperialism (a separate cause) rather than alliance purpose. So the correct reason is providing protection and support among member nations.

Answer:

The option "providing protection and support among member nations" (the third option in the list)