The correct answer is C, as Gorbachev's economic reform efforts were called Perestroika.
Perestroika was a movement that wanted to reform the Soviet communism by developing a new structure of the internal economy of that country, which was implemented throughout its territory by Mikhail Gorbachev, a month after he took power. The vision that Mikhail Gorbachev had for the future was, fundamentally, to reorganize the socialist system in order to preserve it. Among his plans for change was that Soviet society could be transformed so that it was ready and could contribute to the creation of a new economic system within socialism, in the Soviet Union. This process was full of conversions towards democracy in politics and the members of the Kremlin, bringing with it a huge amount of consequences in the economy and in society, which culminated in the Gorbachev era and the consequent dissolution of the USSR.