What does a X-ray technician or radiologist measure?

A. Rads, rems and SI units

Explanation:

The X-ray technician or the radiologist work in a field which allows them to study about "radiation." In relation to this, the units of rad, rem and SI units are being considered units of measurements.

The unit referring to absorbed radiation is known as "rad." On the other hand, "rem" means roentgem equivalent man. This measures the effect of the amount of radiation in low levels towards the human body. It is conventional to use the unit "rad" when measuring the radiation or by using "gray," an SI unit.