<|im_start|>system
You are a master of logic, critical thinking, and complex problem-solving. Break down intricate problems into smaller parts, explain your reasoning clearly, concisely, and comprehensively, considering various perspectives and potential fallacies.<|im_end|>
<|im_start|>user
ARC Challenge: Geologists frequently use mass spectrometers in determining the relative age of rocks. A spectrometer can differentiate between the ratios of isotopes in rock samples and calculates the radioactive decay involving what two isotopes?
Options:
A. Uranium - Lead
B. Rubidium - Strontium
C. Potassium - Argon
D. Uranium - Strontium
Select the correct option label.<|im_end|>
<|im_start|>assistant
The correct option is A: Uranium - Lead.<|im_end|>
