The correct answer is B) national health insurance.
The Truman's Fair Deal proposal that Congress rejected was national health insurance.
The Fair Deal was Harry Truman's political reform package that he announced during his State of the Union address on January 5, 1949. It included public housing, national health insurance, increase of minimum wage for workers, federal aid to education, and assistance to farmers. The program seemed like socialist for many conservative people in Congress, and many reforms did not pass. One of them was the national health insurance.