According to the universal law of gravitation everything has a gravitation force because everything has mass not everything has a gravitational force because not everything existed when gravity first existed gravity is uniform across the universe gravity only depends upon the mass of an object

The correct answer is:

a. everything has a gravitation force because everything has mass

In fact, the universal law of gravitation states that every object with mass M exerts an attractive, gravitational force to any other object with mass m, and the size of this force is given by:

where G is the gravitational constant, and r is the distance between the two objects.

the answer is c) an oak tree