Which of the following events prompted the ussr to form the warsaw pact?
a) the enactment of the marshall plan in 1948
b) the berlin airlift in 1948 and 1949
c) the creation of nato in 1949
d) the addition of west germany to nato in 1955

The correct answer is D. The event that prompted the USSR to form the Warsaw Pact was the addition of West Germany to NATO in 1955.

Explanation:

The Warsaw Pact was a military alliance between the Soviet Union and Eastern Bloc countries during Cold War.

The treaty was established as a defense pact directed at NATO, which had been established in 1949. An important event that led to the formation of the Warsaw Pact was West Germany's re-armament and NATO membership on May 9, 1955. The pact was signed in Warsaw on May 14, 1955, and entered into force on June 5, 1955. The Soviet Union had previously signed bilateral defense agreements with most of the Warsaw Pact member states. The change to a multilateral agreement helped to increase the Soviet Union's prestige as an international superpower.  

On November 3, 1956, Hungary's new Prime Minister Imre Nagy declared that Hungary would withdraw from the Warsaw Pact. On November 4, the country was invaded by the Soviet Union. About 4,000 Hungarians were killed, several thousands imprisoned and about 200,000 fled.

On the night between August 20 and 21, 1968, the Warsaw Pact invaded Czechoslovakia to crush Alexander Dubček's new and more liberal regime. It was the only joint military operation the Warsaw Pact undertook.

It lasted until the Cold War was over, and member states began to withdraw in 1991. The pact was officially dissolved on July 1, 1991.

b) a state law could be declared illegal if it contradicted the constitution.

explanation:

the conflict of this case originated when james w. mcculloch, a cashier of the baltimore branch of the second bank of the united states that the congress had chartered in 1816, refused to pay a tax imposed by the maryland state.

in the case, the state of maryland appealed that the establishment of a second bank was unconstitutional since the constitution didn't say anything about granting that power to congress. however, the case determined that even if such right wasn't specifically stated in the constitution, it was part of the "implied powers" of the government enunciated in article i, section 8.

the case also eliminated maryland's legislation to impose taxes to a national bank, asserting that even though the states retained the power of taxation, the constitution's laws are supreme and can not be controlled by the states, therefore, if a state law contradicts the constitution, it should be declared illegal.

explanation: