The child of 'O' group has 'B' group father .The genotype of the father will be :

Options

A. `I^(O)I^(O)`
B. `I^(B)I^(B)`
C. `I^(A)I^(B)`
D. `I^(B)I^(O)`

Answer

To determine the genotype of a father with a B blood group whose child has an O blood group, we need to understand the inheritance of blood groups.

### Step-by-Step Solution:

1. **Understand Blood Group Genetics**:
- Human blood groups are determined by three alleles: IA (A), IB (B), and IO (O).
- IA and IB are co-dominant, while IO is recessive.

2. **Identify the Child's Genotype**:
- The child has an O blood group, which means the genotype must be IO IO (homozygous for the O allele).

3. **Determine Possible Genotypes for the Father**:
- The father has a B blood group. The possible genotypes for a B blood group individual can be:
- IB IB (homozygous for B)
- IB IO (heterozygous, carrying one O allele)

4. **Analyze the Inheritance**:
- For the child to have an O blood group (IO IO), the father must contribute one IO allele.
- Therefore, the father cannot be IB IB because he would not have an O allele to pass on.

5. **Conclude the Father's Genotype**:
- The only possible genotype for the father that allows for a child with an O blood group is IB IO.

### Final Answer:
The genotype of the B group father is **IB IO**.

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