Which blood group is an example of both co-dominance and multiple allelism?
Blood group AB is an example of co-dominance (both A and B are expressed) and multiple allelism (three alleles: IA, IB, and i).
Ref: NCERT Class 12 Biology Chapter 4: Principles of Inheritance and Variation Non-Mendelian Inheritance - Incomplete Dominance Co-dominance Multiple Alleles