In 1972, nixon became the first us president to initiate a “cold war” with communist nations. visit china while still in office. withdraw official us recognition of china. officially recognize the soviet union.

The right answer is Nixon became the first US president to  visit China while still in office. Lets understand why:

Richard Nixon (1913-1994) was the 37th president of the US for the Republican Party between 1969 to 1974. Seeing an opportunity to articulate himself in foreigner affairs, since the Congress was dominated by Democrats, Nixon moved his sights to China.  Since 1945 the US was not the nuclear monopolist and others centers of power were in the rise. Communist China had replaced the US as the Soviet's Union most threatening competitor and this was a great opportunity for Nixon's actions.

Both nations, the US and China, were consumed from prolonged wars and domestic conflicts. And also, excited to resist Soviet expansionism around the world. The result was a scientific and cultural agreement between the two nations, the US president to  visit China while still in office in 1972.

d)to gain support for the independence movement.

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