What was perestroika?

a. a soviet policy of nuclear disarmament
b. a soviet policy to make the economy more open to foreign competition and individual citizens
c. a soviet policy to increase military spending
d. a soviet policy of making the government more open

The answer is 'B'.
Perestroika was a Soviet policy to make the economy more open to foreign competition and individual citizens.
Mikhail Gorbachev attempted to reconstruct the economic system of the Communist Party.
Example: Ending price controls
Glasnost refers to the government becoming more open.