For two point charges $q_1$ and $q_2$ separated by a distance $r$, the force $F$ is described by the equation $F = \frac{k q_1 q_2}{r^2}$, where $k$ is a constant. What are the SI base units of $k$?
- A$\text{kg m}^3\ \text{s}^{-4}\ \text{A}^{-2}$
- B$\text{kg m}^3\ \text{s}^{-4}\ \text{A}^{-2}$
- C$\text{kg m}^3\ \text{A}^2$
- D$\text{kg m}^3\ \text{A}^{-2}$