Each of the following statements regarding the point of entry is correct EXCEPT one. Which one is the EXCEPTION?

a. Incorrect point of entry results in cone cut error.
b. Care must be taken to center the image receptor within the beam of radiation.
c. The open end of the PID should be placed two inches from the patient's skin.
d. An image receptor holder with an external aiming device aids in locating the point of entry.

c. The open end of the PID should be placed as close to the patient's skin as possible, without touching, to avoid an underexposed radiograph. As the beam of radiation spreads out, less radiation is available to strike the film and produce a diagnostic-quality radiograph.