I believe the answer would be D. The Moon Orbits the Earth.
Hope this helps.
D , over a period of time. I know becuase i have studied science forever almost. But Yes, over a period of time is correct.
They are both are types of explanations.
The medical record is a powerful tool that allows the treating physician
to track the patient’s medical history and identify problems or
patterns that may help determine the course of health care.