Which of the following terms is used to describe the equivalent dose concerning the biological effect of radiation?

The term that describes the equivalent dose concerning the biological effect of radiation is "Roentgen equivalent man," commonly abbreviated as REM. This unit is specifically used to measure the biological effects of radiation on human tissue, taking into account the type and energy of the radiation absorbed. REM is significant because it allows for the comparison of the biological impact of different types of radiation, factoring in the varying degrees of harm they can cause to living organisms.

In contrast, the other terms listed refer to different concepts in radiation measurement. The Roentgen is a unit used to measure exposure to ionizing radiation but does not account for biological effect. The Radiation Absorbed Dose (RAD) measures the amount of energy absorbed per unit mass of tissue without considering the biological response. Curies measure radioactivity but do not provide information about the biological impact of radiation on human health. Therefore, Roentgen equivalent man is the most appropriate term that correlates the physical amount of radiation absorbed with its potential biological effects.