The mass of an object causes the gravitational force exerted by that object, and an asteroid is a rock-like object with an irregular shape. Given these facts, what causes the gravitational force exerted by an asteroid among the following options:
- a tree falling
 - flow of electrons
 - the shape of the asteroid
 - kinetic energy
 - solid, liquid, gas
 - the mass of the asteroid
 - the sound of the asteroid
 - the color of the asteroid


 

      the mass of the asteroid   