In ABO system of blood grouping, transfusion is not possible from

Options

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

Answer

To solve the question regarding blood transfusion compatibility in the ABO blood grouping system, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the ABO Blood Groups**:
- There are four main blood groups in the ABO system: A, B, AB, and O.
- Each blood group has specific antigens and antibodies.

2. **Identify Antigens and Antibodies**:
- **Blood Group A**:
- Antigen: A
- Antibody: B
- **Blood Group B**:
- Antigen: B
- Antibody: A
- **Blood Group AB**:
- Antigens: A and B
- Antibodies: None (universal acceptor)
- **Blood Group O**:
- Antigens: None
- Antibodies: A and B (universal donor)

3. **Determine Compatibility**:
- Blood group A can donate to A and AB.
- Blood group B can donate to B and AB.
- Blood group AB can only donate to AB but can receive from all groups.
- Blood group O can donate to all groups but can only receive from O.

4. **Analyze the Options**:
- **Option A**: A to AB - Possible (A can donate to AB).
- **Option B**: B to AB - Possible (B can donate to AB).
- **Option C**: O to O - Possible (O can donate to O).
- **Option D**: A to O - Not possible (A cannot donate to O because O has antibodies against A).

5. **Conclusion**:
- The transfusion is not possible from A to O. Therefore, the correct answer is **Option D**: A to O.