The correct answer is:
C. To appeal to the dissatisfied, multi-ethnic population of the Soviet Union.
Gorbachev was not trying "to establish his dominance," as the other answer here had suggested. When Gorbachev came into leadership in the USSR, the Soviet economy was struggling and there were dissidents across the spectrum of the country who called out for reforms and changes.
In 1985, Mikhail Gorbachev proposed policies of perestroika (restructuring) and glasnost (openness) in the Soviet Union. Perestroika meant allowing some measure of private enterprise in the Soviet Union. Glasnost meant allowing a bit of freedom in regard to speech and publication.
