Question

In a disputed percentage case, the child is blood type AB while the mother is blood type AB. What are the possible blood type(s) for the father?

Select all that apply.
AB
O
B
A

Answer 1

One allele (A, B or O) is given by each parent,

If the mother gave A then the dad must have given B

If the mother gave B then the dad must have given A

The dad cannot be O.