Jonas Salk Developed the First Polio Vaccine

Multiple Choice

Jonas Salk developed the first polio vaccine. When he accepted the Nobel Prize, he said, "The greatest reward for serving others is the opportunity to do further service." Salk's statement suggests that his efforts were motivated by

A) fame gained from research.
B) the power to control production of a valuable substance.
C) curiosity to answer scientific questions.
D) altruism.