2. For the ellipse $\frac{x^{2}}{12}+\frac{y^{2}}{3}=1$, the foci are $F_{1}$ and $F_{2}$, and point $P$ is on the ellipse. If the midpoint of segment $P F_{1}$ lies on the $y$-axis, then, $\left|P F_{1}\right|$ is ( times $\left|P F_{2}\right|$.
(A) 7
(B) 5
(C) 4
(D) 3
2. A.

The x-coordinate of point $P$ is 3, so the absolute value of the y-coordinate of point $P$ is $\sqrt{\frac{3}{2}}$. Meanwhile, $P F_{2}$ is perpendicular to the $x$-axis, hence
$$
\left|P F_{1}\right|+\left|P F_{2}\right|=4 \sqrt{3} \text{. }
$$