Final answer:
American and South Korean college students were most satisfied by the fulfillment of self-transcendence and self-actualization needs, as outlined in Maslow's hierarchy of needs.
Step-by-step explanation:
The satisfaction of self-transcendence and self-actualization were the top two contributors to American and South Korean collegians' peak moments in the past week. These concepts relate to the upper tiers of Abraham Maslow's hierarchy of needs, which categorizes human needs from the most basic physiological ones to the higher-level psychological needs, with self-actualization at the top. Achieving self-actualization is seen as realizing one's full potential and is only possible when lower-level needs have been met.