What do astronomers refer to as the retrograde motion of the planets? A. apparent movement of the planets eastward in a single night B. apparent movement of the planets westward in a single night C. apparent movement of the planets eastward from night to night D. apparent movement of the planets westward from night to night

Astronomers refer to as retrograde motion of the planets to an apparent movement of the planets westward from night to night.What is a retrograde motion?The retrograde movement or the retrogradation of the planets is the apparent movement that a planet makes in the opposite direction to the other bodies that make up the system where it is. This movement is actually an optical illusion that occurs due to the difference in speed between the different planets, looking as if one of them were moving backwards from east to west.Therefore, we can confirm that the correct answer is option D. apparent movement of the planets westward from night to night.To learn more about retrograde motion visit: https://brainly.com/question/831223#SPJ1