What was the purpose of the Warsaw Pact?

The Warsaw Pact was a military alliance formed by Turkey and Greece to aid nations struggling against communist movements.

The Warsaw Pact was a military alliance formed by the Soviet Union and its satellite states to defend one another if attacked.

The Warsaw Pact was a military alliance formed by nations of Western Europe and North America to counter Soviet expansion.

The Warsaw Pact was a military alliance formed by the United States and Britain to supply West Berlin through a massive airlift.

The correct answer is: The Warsaw Pact was a military alliance formed by the Soviet Union and its satellite states to defend one another if attacked.