Final answer:
12 men have walked on the moon as part of the Apollo program between 1968 and 1972.
Step-by-step explanation:
The correct answer is 3) 12 men have walked on the moon. The United States sent 12 astronauts to land on the moon as part of the Apollo program between 1968 and 1972. These missions included the historic Apollo 11, which landed the first astronaut on the moon, Neil Armstrong, on July 20, 1969. The last human to set foot on the moon was Eugene Cernan during the Apollo 17 mission in December 1972.