Answer and explanation

Correct answer: C. Carbon-14

  1. Step 1: Isotopes have the same number of protons but different numbers of neutrons. Answer: Carbon-14. Why not the others: Nitrogen-14, Oxygen-16 and Boron-11 don't fit.

Practise more Biology, chemistry and physics reasoning.

Free questions with an explanation for every one, and full timed GAMSAT (Graduate Medical School Admissions Test) mock tests.