Question

Assertion (A): ABO blood grouping in humans is an example of multiple allelism.
Reason (R): More than two genes in a population govern the same character in ABO blood grouping in humans.

• A. Both (A) and (R) are true and (R) is the correct explanation of (A).
• B. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
• C. (A) is true, but (R) is false.
• D. (A) is false, but (R) is true.

Hint:

Multiple alleles = one gene with more than two allele forms, not multiple genes.

Answer 1

The Correct Option is C

Step 1: ABO blood grouping is governed by a single gene (I) with three alleles — \( I^A, I^B, \text{and } i \), which is an example of multiple allelism.
Step 2: The reason incorrectly states that more than two genes are involved. In reality, it is one gene with more than two alleles.
Step 3: Assertion is true, reason is false.