For a PA Axial Cranial Projection (Caldwell Method), the

For a PA axial cranial projection (Caldwell method) , the
1) midsagittal plane is aligned perpendicular to the IR.
2) central ray is angled 15 degrees caudally.
3) OML is aligned perpendicular to the IR.
4) central ray is centered to the nasion.

A) 1 and 3 only
B) 2 and 4 only
C) 2, 3, and 4 only
D) 1, 2, 3, and 4