Assertion: DNA is considered to be better genetic material than RNA for most organisms.
Reason: 2′-OH group present in DNA makes it labile and less reactive.

Assertion (A) is true but Reason (R) is not correct.

The correct answer is Option (3)- Assertion (A) is true but Reason (R) is not correct.

The genetic material should be stable enough not to change with different stages of life cycle, age or with change in the physiology of the organism. The DNA strands being complementary, if separated by heating come together, when appropriate conditions are provided. Further, 2-OH group present at every nucleotide in RNA is a reactive group and makes RNA labile and easily degradable. RNA is also now known to be catalytic, hence reactive. Therefore, DNA chemically is less reactive and structurally more stable when compared to RNA. Therefore, among the two nucleic acids, the DNA is a better genetic material.