| 1. | Mother is homozygous for ‘A’ blood group and father is heterozygous for ‘B’ |
| 2. | Mother is heterozygous for ‘A’ blood group and father is homozygous for ‘B’ |
| 3. | Both mother and father are heterozygous for ‘A’ and ‘B’ blood group, respectively |
| 4. | Both mother and father are homozygous for ‘A’ and ‘B’ blood group, respectively |