The reason that the Earth's surface has so few meteor craters compared to other nearby bodies in the solar system is that

a. the Moon blocked almost all of the meteors that otherwise would have hit the Earth.  

b. the atmosphere causes all objects entering from space to burn up before they hit the ground.

c. the Earth's surface has been modified by various forces that cover or remove traces of the craters.

d. all meteorite impacts break the crust and release lava from the mantle to fill in the hole.