In the regular quadrilateral pyramid ABCDP, the diagonals of the base, AC and BD intersect at point O. Determine the set of points common for plane (ACP)
and the plane, say µ, which contains the line BD and is parallel to the lateral
edge AP.
A. Point O only
B. Line that contains point P and parallel to line BD.
C. Line through point O, parallel to edge AP and intersecting edge DC at
its midpoint.
D. Line through point O, parallel to edge AP and intersecting edge CP at
its midpoint.

(rsm 903H geo)