Why was the Cuban missile crisis significant?

(1 point)
Responses

Cuba threatened to invade the United States.
Cuba threatened to invade the United States.

It came close to starting a full-scale nuclear war.
It came close to starting a full-scale nuclear war.

The United States almost fell under communist rule.
The United States almost fell under communist rule.

It promoted nuclear research in the Soviet Union.

It led to improved communication between the United States and the Soviet Union.