For an AP neonatal or infant chest projection, the

1. central ray is centered to the midsagittal plane at the level of the mammary line.
2. longitudinal collimation should be open enough to include the upper airway.
3. head faces straight up, without rotation.
4. central ray is angled 5 degrees caudally.
a. 1 and 2 only
b. 2 and 4 only
c. 1, 2, and 3 only
d. 1, 2, 3, and 4

D