Fact 1: The mass of an object causes the gravitational force exerted by that object. Fact 2: An asteroid is a rock-like object with an irregular shape. Given the two facts above, what causes the gravitational force exerted by an asteroid?

Available options:
(i) a tree falling.
(ii) flow of electrons.
(iii) the shape of the asteroid.
(iv) kinetic energy.
(v) solid, liquid, gas.
(vi) the mass of the asteroid.
(vii) the sound of the asteroid.
(viii) the color of the asteroid.
Answer:
(vi)