Which of the following cases of blood tranfusion will not lead to clumping of RBCs?

Options

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

Answer

To determine which case of blood transfusion will not lead to clumping of red blood cells (RBCs), we need to understand the compatibility of different blood groups based on their antigens and antibodies.

### Step-by-Step Solution:

1. **Understand Blood Groups and Their Antigens:**
- Blood group A has A antigens on the surface of its RBCs.
- Blood group B has B antigens on the surface of its RBCs.
- Blood group AB has both A and B antigens on the surface of its RBCs.
- Blood group O has no antigens on the surface of its RBCs.

2. **Understand Antibodies Produced by Each Blood Group:**
- Blood group A produces anti-B antibodies.
- Blood group B produces anti-A antibodies.
- Blood group AB does not produce any antibodies.
- Blood group O produces both anti-A and anti-B antibodies.

3. **Identify Clumping Scenarios:**
- Clumping occurs when antibodies in the recipient's blood react with the antigens in the donor's blood.
- If a person with blood group A receives blood from group B, the anti-B antibodies will react with the B antigens, causing clumping.
- If a person with blood group B receives blood from group A, the anti-A antibodies will react with the A antigens, causing clumping.
- If a person with blood group AB receives blood from any group (A, B, or O), there will be no clumping because AB does not produce any antibodies against A or B antigens.
- If a person with blood group O receives blood from A or B, the anti-A or anti-B antibodies in O will react with the respective antigens, causing clumping.

4. **Identify the Universal Recipient and Donor:**
- Blood group AB is known as the universal recipient because it can receive blood from any group without causing clumping.
- Blood group O is known as the universal donor because it has no antigens to react with any recipient's antibodies.

5. **Conclusion:**
- The only case where clumping will not occur is when blood group AB (recipient) receives blood from blood group O (donor). This is because O has no antigens to react with the antibodies present in AB.

### Final Answer:
The case of blood transfusion that will not lead to clumping of RBCs is when **blood group AB receives blood from blood group O**.