Given below are two statements. One is labelled Assertion (A) and the other is labelled Reason (R).
Assertion (A):¹⁵N is a radioactive isotope of nitrogen, and it cannot be separated from ¹⁴N only based on density.
Reason(R): Taylor and colleagues performed experiments on Vicia faba to prove that DNA in chromosomes replicates semi-conservatively.
In the light of the above statement, choose the most appropriate answer.