Answer:
bounce the laser light back to Earth
Step-by-step explanation:
The Lunar laser ranging retroreflector was used for the first time in the Apollo 11 launch mission. Later, it was used during the Apollo 14 and Apollo 15 mission.
The laser reflectors are made of the reflecting mirrors which can reflect the laser light in the same direction from where it is coming. These devices were placed on the moon during the mission and are used till today.
The laser light is pointed from the Earth to the device placed on the moon which reflects or bounce the light back to the Earth. This takes the time and the total time is measured and is used to calculate the distance between the Earth and the Moon, to calculate the rotation of the Moon and many other factors related to the Moon.
Thus, the selected option is the correct answer.