Question

why was the united nations formed?
to promote communism
to engage in armed conflict
to defend nations against attack
to promote international peace

Explanation:

The United Nations was established after World War II with the main goal of maintaining international peace and security, developing friendly relations among nations, and promoting social progress, better living standards, and human rights. It was not formed to promote Communism, engage in armed conflict, or just defend against attack in a narrow - sense. Its overarching aim is peace - related.

Answer:

to promote international peace