Final answer:
Added filtration and inherent filtration contribute to the 'total' filtration of the useful X-ray beam.
Step-by-step explanation:
In the context of X-rays, the two types of filtration that contribute to the 'total' filtration of the useful X-ray beam are added filtration and inherent filtration. Added filtration refers to the additional filters that are placed in the path of the X-ray beam, such as aluminum or copper, to remove low-energy photons. Inherent filtration is the filtration that naturally occurs as the X-ray beam passes through the X-ray tube, table, and grid.
Therefore, the correct answer is option 1 and option 2: added filtration and inherent filtration.