If the distance between two objects is increased to four times the original distance, how will that increase change the force of attraction between the objects?

Gravitational force becomes sixteen times lesser. The strength of the gravitational force between two objects is dependent on their mass. Gravitational force will be weaker if the objects move further away from each other.
This was used to solve for the gravitational force,
G = gravitational constant 
m = mass of the first object 
M = mass of the second object 
d = distance between the two objects 

[G * (m*M) / 16d^2] = 1/16

The answer is going to be a because ik that i’m right