Question

The tendency of two masses alone in the universe to drift together is a result of

Answer 1

It is the result of Gravity D)

Answer 2

It is as a result of gravity.  (D)

This is as stated by Newton's law of universal gravitation. That two objects in the universe attract one another with a force that is proportional to the product of their masses and inversely proportional to the square of the distance apart.

The constant of proportionality is the Universal Gravitational Constant.

G = 6.673 × 10⁻¹¹ Nm²kg⁻²