OPT: a). Calcium carbonate b). dinosaurs c). a barometer d). electron microscope e). a thermometer f). a decay curve g). chemical equations h). Physical weathering
Given those answer options, answer the question: You are presented with the quiz "What is used to determine the age of fossils?"   But you don't know the answer, so you turn to your teacher to ask for hints. He says that "radioactive dating is used to determine the age of fossils" and "radioactive dating requires the use of a decay curve".   So, what's the best answer to the question?
A:
f).