PLEASE HELP ME!!! IT'S THE LAST DAY AND I HAVE A D IN THIS CLASS!!! PLZZZ HELP

What was the main reason the Soviet Union crumbled in the 1980s?
A. Glasnost led to rebellion against communist rule around the world.
B. The Soviet economy could not match U.S. military spending while meeting citizens’ demand for consumer goods.
C. Policies introduced by Mikhail Gorbachev resulted in the Soviet Union losing its main source of income.
D. The United States convinced Soviet leaders to abandon communist economic policies.