`P(vec p) and Q(vec q)` are the position vectors of two fixed points and `R(vec r)` is the position vectorvariable point. If R moves such that `(vec r-vec p)xx(vec r -vec q)=0` then the locus of R is

Options

A. A plane containing the origin O and parallel to two non- collinear vector vector `OP and OQ`.
B. the surface of a sphere described on PQ as its diameter.
C. a line passing through the points P and Q.
D. a set of lines parallel to the line PQ.

Answer

(c)