For PA axial oblique cervical projection,

1. the midcoronal plane is aligned at a 45-degree angle with the IR.
2. the central ray is angled 15 degrees caudally.
3. the head's midsagittal plane is aligned perpendicular to the IR.
4. an increased caudal angle is needed to demonstrate the lower vertebrae on a severely kyphotic patient.
a. 1 and 2 only
b. 1 and 3 only
c. 2 and 3 only
d. 1, 2, and 4 only

D