Which statement is true about the relationship between mass and weight?

a
Mass is dependent on volume, while weight is dependent on the number of atoms in an object.
b
Mass and weight are the same thing and can be used interchangeably.
c
Mass does not change in an object, but the weight of the object is affected by gravity.
d
Mass increases with increasing gravity, while weight does not change with gravity.

c) Mass does not change in an object, but the weight of the object is affected by gravity.