Earth Scientists are able to tell the age of rocks using radiometric dating. Choose the best description of how this works.
A) Scientists don't know how much radioactive material was in rocks when they formed so radiometric dating is innacurate. It is also impossible for an atom of one element to turn into an atom of another element.
B) Radioactive materials spontaneously decay into atoms of other elements. Each radioactive material has a characteristic half-life, which is the time required for one-half of the atoms in a sample to decay to atoms of other elements. The older a rock sample is the more radioactive material will have been converted to decay product(s). Instruments can accurately measure the amount of radioactive material and the amount of resulting decay product in a rock sample. By comparing the ratio of these two quantities, the age of a rock sample can be determined, which is referred to as radiometric age dating.
C) Radiometric dating is dangerous work because the radioactive material in the rocks is a human health hazard.
D) Rocks accumulate radioactive material over time from a combination of cosmic rays, human activities and geologic processes. Analytical instruments can accurately measure the amount of this material in rocks which scientists use to estimate when the rock formed.