What caused relations between the united states and the soviet union to begin to change in the early 1980s? check all that apply.

You didn't list options, so I'll simply give some history here.

When President Ronald Reagan came into office in 1981, he took a hard stance toward the Soviet Union.  Where previous leaders of the nations had pursued detente and nuclear arms reduction, Reagan spoke of the Soviet Union as the "evil empire" and, in 1983, proposed a major new space-based missile defense program, the Strategic Defense initiative. 

But in 1985, the positions of the two countries began to shift again.  In March 1985, Mikhail Gorbachev proposed policies of perestroika (restructuring) and glasnost (openness) in the Soviet Union.  In November 1985, Reagan and Gorbachev met in person for the first of several summit meetings they would have, and developed a personal relationship.  

In 1987, Reagan gave a speech in Berlin (a city divided between democratic West Berlin and communist East Berlin).  In that speech he issued a famous personal appeal to Gorbachev, saying:  

uncle sam would be tossing and turning in his grave : *)