How was the Soviet orbital flight in 1961 related to the Apollo program?

The correct answer is:

It served as inspiration for the creation of the Apollo program.

Explanation:

The space race created during the Cold War between the Soviet Union and the United States after WWII, served as motivation for many technological advances that brought mankind closer to the space.

After the launch of the Soviet space capsule Vostok 1, which carried the first man out to space (Soviet Yuri Gagarin) on April 12, 1961. The United States was inspired by the Soviet program and NASA created the Apollo program (1961-1972) to achieve preeminence in space, to develop technology and to explore and work in the lunar environment. The Apollo program became the first program to carry a man to the moon on the Apollo 8 space capsule on 1969.

It inspired the United States to establish the Apollo program.