Assertion:A woman of blood group AB when married to an O group man will never get an AB group child because
Reasoning:Blood groups O gene is dominant over A,B or AB

Options

A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not a correct explanation of Assertion
C. Assertion is true but Reason is false
D. Assertion is false but Reason is true

Answer

To solve the question, we will analyze the assertion and reasoning step by step.

### Step 1: Understand the Blood Groups
- Blood group is determined by the presence of specific alleles.
- The alleles for blood groups are:
- **IA** for blood group A
- **IB** for blood group B
- **i** (or IO) for blood group O
- Blood group AB has both IA and IB alleles, while blood group O has two recessive alleles (ii).

### Step 2: Analyze the Assertion
- The assertion states that a woman with blood group AB (genotype IA IB) married to a man with blood group O (genotype ii) will never have an AB blood group child.
- Let's determine the possible blood groups of their children:
- The woman can produce gametes with IA and IB.
- The man can only produce gametes with i.

### Step 3: Perform the Genetic Cross
- The possible combinations of gametes from the woman and man are:
- IA (from woman) + i (from man) = Blood group A (genotype IA i)
- IB (from woman) + i (from man) = Blood group B (genotype IB i)

- Therefore, the possible blood groups of their children are:
- A (IA i)
- B (IB i)

- There are no combinations that would result in blood group AB (IA IB) or O (ii).

### Step 4: Conclusion on the Assertion
- The assertion is **true**: A woman of blood group AB married to a man of blood group O will never have an AB blood group child.

### Step 5: Analyze the Reasoning
- The reasoning states that the blood group O gene is dominant over A, B, or AB.
- This is **incorrect**: The O blood group is recessive. It does not dominate over A or B; rather, A and B are co-dominant.

### Final Conclusion
- The assertion is true, but the reasoning is false.

### Summary
- **Assertion**: True
- **Reasoning**: False