Inherent Filtration in the Dental X-Ray Tubehead

Inherent filtration in the dental x-ray tubehead:

A) Includes filtration that takes place when the primary beam passes through the glass window of the x-ray tube, the insulating oil, and the tubehead seal.
B) Includes the placement of aluminum discs in the path of the x-ray beam between the collimator and the tubehead seal.
C) Alone meets the standards regulated by state and federal law.
D) Is equivalent to approximately 5.0 mm of aluminum.