Answer:
D
Step-by-step explanation:
Absolute age is defined as the numeric age of fossils.
To identify the absolute age of a fossil, the amount of certain radioactive elements in the rock are measured. When fossils are formed in the rocks, a small amounts of radioactive elements is included in it. The process to identify age of fossil using radioactive elements is known radiometric dating. So, radioactive isotope and its decay product gives absolute age of fossils.
Hence, the correct answer is "D".