Concept:A solar eclipse is visible only where the Moon's shadow touches Earth.
Explanation:The Moon is much smaller in diameter than Earth, so its shadow covers only a narrow region on Earth's surface.
During a total solar eclipse, the Moon blocks the Sun completely only for observers inside this small shadow path.
People outside this path may see a partial eclipse, but not a total eclipse.
Since Earth's diameter is larger than the Moon's, the Moon's shadow cannot cover a large portion of Earth.
Therefore, a total solar eclipse is seen by people on only a small portion of Earth's surface.
Answer:D. earth is larger in diameter than the moon.