How did Natan Sharansky resist political oppression during the Cold War?

A. He convinced the Soviet Union to support Palestinians who were
forced to leave Israel.

B. He spoke out against the Soviet Union's refusal to allow Jews to
immigrate to Israel.

C. He organized an anti-communist rebellion along with members of
the Soviet military.

D. He reformed the Soviet Union's government to end the country's
anti-Semitism.