At 8:00 P.M . on a clear night, Tao observed groups of stars in the night sky. Three hours later on the same night, the groups of stars appeared in a different location in the night sky. Which of the following explains why the groups of stars appeared in a different location in the night sky after three hours?
A. Earth had tilted farther away from the stars.
B. Earth had rotated on its axis.
C. Earth had moved closer to the stars.
D. Earth had orbited the sun.