The normal at a point P on the ellipse x2+4y2=16 meets the X -axis at Q . If M is the mid-point of the line segment PQ , then the locus of M intersects the latusrectum of the given ellipse at the points
a. (±235,±72)
b. (±235,±419)
c. (±23,±71)
d. (±23,±743)