Which best describes how radiocarbon dating is performed on a fossil?
a. The amount of carbon-14 that decayed is determined by comparing the ratio of carbon-14 and carbon-12 in the fossil.
b. The half-life of carbon-12 is determined and compared to the half-life of carbon-12 from a more recent fossil.
c. Carbon-14 is extracted from the fossil and its concentration is determined before and after being allowed to decay in the lab.
d. The fossil is left to sit in the lab and the amount of carbon-14 it absorbs from the atmosphere indicated the fossil's age.
Answer: A