According to Newton's law of universal gravitation, the magnitude of the gravitational force between two point masses depends on which two factors?

• A. The sum of the two masses and the distance between their centers (specifically it varies as $\frac{m+M}{r^2}$)
• B. The product of the two masses and the square of the distance between their centers (specifically it varies as $mM{r}^2$)
• C. The product of the two masses and the distance between their centers (specifically it varies as $\frac{mM}{r^2}$)
• D. The difference of the two masses and the distance between their centers (specifically it varies as $\frac{m-M}{r^2}$)

Answer: (C)