Step 1: Understanding the terms:
Glasnost (openness) and Perestroika (restructuring) were reform policies launched to revive the stagnating Soviet economy and open up its political system.
Step 2: Identifying the leader:
These policies were introduced in the mid-1980s by Mikhail Gorbachev, the last General Secretary of the Communist Party of the Soviet Union.
Step 3: Why the other options are wrong:
Stalin (1920s-50s) and Brezhnev (1960s-82) predate these reforms and represent the era of central control the reforms tried to fix; Roosevelt was a US President, unconnected to Soviet policy.
Step 4: Final Answer:
Mikhail Gorbachev introduced Glasnost and Perestroika.