A mother who is blood type AB has a child who is also AB. A potential father is blood type 0. A well-informed geneticist concludes that

Options

A. he cannot be the father
B. the mother of the child is not genetical mother.
C. he is very likely to be the father
D. he or any other male of blood type o could be the father

Answer

To solve the problem, we need to analyze the blood types and genotypes of the mother, potential father, and child.

### Step-by-Step Solution:

1. **Identify the Genotypes:**
- The mother has blood type AB. The genotype for blood type AB is IAIB.
- The potential father has blood type O. The genotype for blood type O is ii (where 'i' represents the recessive allele).

2. **Determine Possible Gametes:**
- The mother (IAIB) can produce two types of gametes: IA and IB.
- The father (ii) can only produce one type of gamete: i.

3. **Perform a Punnett Square Analysis:**
- We can set up a Punnett square to determine the possible genotypes of the offspring from the mother and father.
- The possible combinations from the mother’s gametes (IA and IB) and the father’s gamete (i) would be:
- IA from mother and i from father → IAi (which is blood type A)
- IB from mother and i from father → IBi (which is blood type B)

4. **Analyze the Offspring Blood Type:**
- The child is reported to have blood type AB, which corresponds to the genotype IAIB.
- Since the potential father can only contribute an 'i' allele, he cannot contribute to the AB genotype.

5. **Conclusion:**
- Therefore, the conclusion is that the potential father with blood type O cannot be the biological father of the child with blood type AB. The child must have a different biological father.

### Final Conclusion:
A well-informed geneticist would conclude that the potential father with blood type O cannot be the biological father of the child with blood type AB.