The correct answer is D) he refused to crush rebellions in Eastern Europe.
Mikhail Gorbachev had trouble retaining support from hard-line communists because he refused to crush rebellions in Eastern Europe.
When everything seemed that the Soviet Union would never change, Mikhail Gorbachev started a series of changes called perestroika and glasnost that transformed the world scenario and the relationships between Russia and the West World. Gorbachev opened the door to foreign investment, gave some liberties to the soviet people, and ended up dissolving the Soviet Union on December 26, 1991.