Which United States president secured a détente with both China and the Soviet Union, ended U.S. involvement in Vietnam, and resigned after the Watergate scandal?

AJimmy Carter

BRichard Nixon

CRonald Reagan

DGeorge H.W. Bush

As the Cold War came to a close, _____ emerged as the only superpower.

ARussia

Bthe United States

Cthe European Union

Dthird world countries