Radioactive Isotopes Are Used in Dating Materials from the Distant $\pm$

Radioactive isotopes are used in dating materials from the distant past.Which of the following statements about radioactive dating techniques is true?

A) It gives the general ages of rock stratA.( $\pm$ 1 million years) .
B) It gives exact ages of rock strata.( $\pm$ 1 year) .
C) It uses a technique in which the degree of radioactive decay is measured,the younger the rock the more radioactive decay.
D) It uses a technique in which the degree of radioactive decay is measured,the older the rock the more radioactive decay.
E) It does not work well with fossil remains that have not absorbed radiation.