A person with antigen A in the RBC and antibody B in plasma belongs to the blood group :

Options

A. A
B. B
C. O
D. AB

Answer

To determine the blood group of a person with antigen A in the red blood cells (RBCs) and antibody B in the plasma, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Blood Group Basics**: Blood groups are determined by the presence of specific antigens on the surface of red blood cells and corresponding antibodies in the plasma. The main blood groups are A, B, AB, and O.

2. **Identify Antigens and Antibodies**:
- Antigen A is present on the RBCs.
- Antibody B is present in the plasma.

3. **Refer to Blood Group Chart**:
- Blood Group A has:
- Antigen: A
- Antibody: Anti-B (NtB)
- Blood Group B has:
- Antigen: B
- Antibody: Anti-A (NtA)
- Blood Group AB has:
- Antigen: A and B
- Antibody: None
- Blood Group O has:
- Antigen: None
- Antibodies: Anti-A and Anti-B

4. **Match the Given Information**:
- Since the person has antigen A, they cannot belong to blood group B, AB, or O.
- The presence of antibody B indicates that the person cannot have blood group B (which would have anti-A antibodies).

5. **Conclusion**: The only blood group that matches the given information (antigen A and antibody B) is **Blood Group A**.

### Final Answer:
The person belongs to **Blood Group A**.

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