Question

Jonas Salk became well known in the early 1950s because he
starred in a popular movie called Rebel without a Cause.
led a movement of people who refused to conform to social trends.
introduced a way to mass-produce homes and reduce their costs.
developed a vaccine that virtually eliminated polio from American society.

Answer 1

developed a vaccine that virtually eliminated polio from American society.

He announced his effective polio vaccine in 1955, which led to mass immunization and a dramatic drop in polio cases.