Each of the progeny have 25% chance of their blood group being O/A/B/AB when their parents are

Options

A. `A xx AB`
B. `O xx AB`
C. `A xx B`
D. `AB xx AB`

Answer

To solve the problem of determining the blood group probabilities of progeny from given parental blood groups, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Parental Blood Groups**: The question states that we need to analyze the blood groups of the progeny based on the blood groups of the parents. The blood groups can be A, B, AB, or O.

2. **Understand Blood Group Genotypes**:
- Blood group A can be represented as either AA or AO.
- Blood group B can be represented as either BB or BO.
- Blood group AB is represented as AB.
- Blood group O is represented as OO.

3. **Analyze Each Cross**:
- **Cross 1: A (AO) x AB**:
- Possible combinations: AA, AO, AB, BO.
- Resulting blood groups: A (50% chance) and B (25% chance) and AB (25% chance). No O blood group.

- **Cross 2: O (OO) x AB**:
- Possible combinations: AO, BO.
- Resulting blood groups: A (50% chance) and B (50% chance). No O or AB blood group.

- **Cross 3: AO x BO**:
- Possible combinations: AB, AO, BO, OO.
- Resulting blood groups: A (25% chance), B (25% chance), AB (25% chance), and O (25% chance).

4. **Determine the Correct Option**:
- From the analysis, only Cross 3 (AO x BO) yields all four blood groups (A, B, AB, O) with equal probabilities of 25% each.

5. **Conclusion**: The correct answer is that each progeny has a 25% chance of having blood groups O, A, B, or AB when the parents are AO and BO.

### Final Answer:
The correct answer is option 3, where the cross is AO x BO, resulting in a 25% chance for each blood group (O, A, B, AB).

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