Which of the following statements about the equation shown is correct? $W = mg$
- A$g$ is a force, $m$ and $W$ are not forces.
- B$m$ is a force, $g$ and $W$ are not forces.
- C$W$ is a force, $g$ and $m$ are not forces.
- DNone of $g$, $m$ and $W$ are forces.