Answer:
Sun, Moon, Earth
Step-by-step explanation:
A solar eclipse occurs when the moon comes in-between the sun and the earth with all the three bodies in alignment. Thus, the moon prevents the rays of the sun to get to the earth and in its stead, cast a shadow of itself on the earth. The casting of the moon's shadow on the earth creates a region of total darkness (umbra) for certain parts of the earth while some other regions at the periphery of the moon's shadow only experience partial darkness (penumbra).
Hence, beginning with the sun, the correct order of the three bodies during a solar eclipse would be the Sun, the Moon, and then the Earth.