The gravitational force between two objects increases as

a mass increases or distance increases.

b mass decreases or distance increases.

c mass increases or distance decreases.

d mass decreases or distance decreases.

Option C.

The gravitational force between two objects is proportional to the product of their mass and inversely proportional to the distance between the two masses.

The formula of the gravitational force between two objects of mass and that are separated by a distance r is:

Where G is the gravitation constant.

You can see that as the masses increase, it also increases the gravitational force. But as the distance between the masses increases, the gravitational force decreases.

Therefore the correct option is the C "mass increases or distance decreases"

The gravitational force between two objects increases as mass increases or distance decreases. (C)

the entire statement is true and correct.  

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