Human blood type is regulated by 3 alleles (A,B,O). Four blood types are possible: A, B, AB, and O. A woman who has blood type A has a son with blood type O. She sues Man #1, whom she claims to be the...

Human blood type is regulated by 3 alleles (A,B,O). Four blood types are possible: A, B, AB, and O.

A woman who has blood type A has a son with blood type O. She sues Man #1, whom she claims to be the father, for child support.  Man #1 suspects he is not the only paternal candidate and requests blood-typing for Man #2. Based on the blood-typing results in the table below who could be the father?

1. Man #1 only


2. Man #2 only


3. Man #1 or Man #2


4. Impossible for either, since the Mother has blood type A