An increase in which factor will decrease the quantity of the x-ray beam?

An increase in filtration in the x-ray beam will decrease the quantity of the x-ray beam. Filtration is the process of selectively removing lower energy (or "soft") x-rays from the beam. This is done using materials that absorb these lower energy x-rays, allowing only the higher energy, more penetrating x-rays to pass through.

When filtration is increased, there is an overall reduction in the number of x-rays that reach the patient and the detector because more of the less useful lower energy photons are absorbed rather than contributing to the image formation. This contributes to a decrease in the overall quantity of the x-ray beam.

In contrast, increasing kilovoltage peak increases the energy of the x-ray beam, leading to higher quantity and quality of x-rays produced. Milliamperage directly increases the quantity of x-rays generated because it determines the number of electrons available to produce x-rays. Additionally, increasing the distance from the x-ray source to the receptor follows the inverse square law, which indicates that the intensity of radiation decreases as the distance increases, affecting the quantity received at the receptor, but this scenario does not directly address an increase in the distance itself leading to an overall decrease in the production of x-rays. Therefore, filtration is the primary factor