A Rem Is

A rem is

A) the amount of radiation that produces 2.1 × 10⁹ units of charge in one cubic centimeter of air.
B) a unit used to measure the amount of radiation absorbed per gram of tissue.
C) a unit that that measures both the energy and the penetrating power of different types of radiation.
D) the SI unit for radiation absorbed.
E) the amount of radioactive substance that undergoes 3.7 × 10¹⁰ disintegrations per second.