Answer:
C) the sun's rays that fall on the moon's surface.
Explanation:
The moon has different aspects and appearance because of the sun's rays that fall on the moon's surface. The shape of the Moon does not change itself, it occurs due to the sunlight. We only see that part of moon which is lit by the Sun. The phases of moon occur because the Sun lit different parts of the moon when the Moon revolves around the Earth so we can say that sun rays are responsible for the changing of shapes of the moon.
