Which of the following representations is correct about blood groups and donor compatibility?

Options

A.
B.
C.
D.

Answer

To determine the correct representation of blood groups and donor compatibility, we need to understand the concepts of blood groups, universal donors, and universal recipients.

### Step-by-Step Solution:

1. **Understand Blood Groups**:
- There are four main blood groups: A, B, AB, and O. Each blood group can be either Rh-positive or Rh-negative.
- Blood group A has A antigens and B antibodies.
- Blood group B has B antigens and A antibodies.
- Blood group AB has both A and B antigens and no antibodies against A or B (universal recipient).
- Blood group O has no antigens but has both A and B antibodies (universal donor).

2. **Identify Universal Donor and Recipient**:
- The universal donor is O negative (O-), meaning it can donate to any blood group without causing an immune reaction.
- The universal recipient is AB positive (AB+), meaning it can receive blood from any blood group without rejecting it.

3. **Evaluate Compatibility**:
- A can donate to A and AB.
- B can donate to B and AB.
- AB can only donate to AB.
- O can donate to A, B, AB, and O.
- A cannot donate to O because O has both A and B antibodies.
- B cannot donate to O for the same reason.

4. **Analyze the Options**:
- **Option 1**: A can give to AB, A, and O. This is incorrect because A cannot give to O.
- **Option 2**: B giving to O is incorrect because O has antibodies against B.
- **Option 3**: AB giving to AB is correct since AB can only donate to AB.
- **Option 4**: O giving to A is correct, but O cannot receive from A due to the presence of A antibodies in O.

5. **Conclusion**:
- The correct representation regarding blood groups and donor compatibility is **Option 3**, which states that AB can donate to AB.