PQ is a normal chord of the parabola `y^2 =4ax` at P, A being the vertex of the parabola. Through P, a line is drawn parallel to AQ meeting the x-axis at R. Then the line length of AR is
(A) equal to the length of the latus rectum (B)equal to the focal distance of the point  P   (C) equal to twice the focal distance of the point  P   (D) equal to the distance of the point  P  from the directrix.

Options

A. the length of latusrectum
B. the focal distance of point P
C. the twice the focal distance of point P
D. the distance of the point P from the directrix

Answer

C