All of the Following Were Evidence of Increased Cold War

All of the following were evidence of increased Cold War tension during the Kennedy presidency except:

A) the U.S. supported Cuban exiles, who launched an unsuccessful assault on Cuba.
B) the Soviets constructed the Berlin Wall to stop the exodus of East Germans.
C) the Soviets supplied arms to Communist guerrillas in Turkey.
D) the Soviets and the U.S. confronted each other over the Soviet military presence in Cuba.