JEE Math Practice Question

Let $P$ be a point on the parabola $y^{2}=4 a x$, where $a>0$. The normal to the parabola at $P$ meets the $x$-axis at a point $Q$. The area of the triangle $P F Q$, where $F$ is the focus of the parabola, is 120 . If the slope $m$ of the normal and $a$ are both positive integers, then the pair $(a, m)$ is

1. A.$(2,3)$
2. B.$(1,3)$
3. C.$(2,4)$
4. D.$(3,4)$