When both the parents are of blood group AB, children would be of blood group

Options

A. A,B, AB and O
B. A,B and AB
C. A and B
D. A,AB and O

Answer

To determine the possible blood groups of children when both parents have blood group AB, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Genotypes of the Parents**:
- Both parents have blood group AB. The genotype for blood group AB is represented as IAIB, where IA is the allele for blood group A and IB is the allele for blood group B.

2. **Determine the Gametes Produced by Each Parent**:
- Each parent can produce two types of gametes: IA and IB.

3. **Set Up a Punnett Square**:
- We can use a Punnett square to visualize the possible combinations of gametes from both parents. The Punnett square will look like this:

```
IA IB
----------------
IA | IAIA | IAIB |
----------------
IB | IAIB | IBIB |
----------------
```

4. **Fill in the Punnett Square**:
- The combinations from the Punnett square are:
- IAIA (which corresponds to blood group A)
- IAIB (which corresponds to blood group AB)
- IAIB (which corresponds to blood group AB)
- IBIB (which corresponds to blood group B)

5. **Count the Genotypes**:
- From the Punnett square, we can see the resulting genotypes:
- 1 IAIA (blood group A)
- 2 IAIB (blood group AB)
- 1 IBIB (blood group B)

6. **Determine the Possible Blood Groups of the Children**:
- The possible blood groups from the combinations are A, AB, and B. There are no combinations that result in blood group O since O requires the genotype ii (no A or B alleles).

### Conclusion:
The children of two parents with blood group AB can have blood groups A, B, or AB.

### Final Answer:
The children would be of blood group A, B, and AB.

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