The amount of carbon-14 remaining in an organism, A, is equal to the product of the initial amount of carbon-14 in the organism, A0, and one-half to the power of n, where n is the number of half-lives the organism has experienced. If a frog initially contained 32 grams of carbon-14 and the half-life of carbon-14 is 5,730 years, how much carbon-14 remains in the frog after 17,190 years? A. 64 grams B. 8 grams C. 4 grams D. 16 grams