Answer: Cold War policies in Southeast Asia are best illustrated by C) the United States' support of South Vietnam.
Step-by-step explanation: The Cold War began after WWII and ended with the fall of the Berlin Wall. It involved two superpowers: the United States and the Soviet Union, each of them with its allies. Some of the policies that the United States adopted during the Cold War were related to its support of South Vietnam, which, unlike North Vietnam, was not under the power of a Communist regime. In contrast, the policies implemented by the Soviet Union were driven by its support to North Vietnam.