The blood group which forms clump with only anti B antiserum

Options

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

Answer

To solve the question regarding which blood group forms a clump with only anti-B antiserum, we can follow these steps:

### Step 1: Understand Blood Groups
Blood groups are determined by the presence or absence of specific antigens on the surface of red blood cells (RBCs). The main blood groups are A, B, AB, and O.

### Step 2: Identify Antigens
- **Blood Group A** has A antigens.
- **Blood Group B** has B antigens.
- **Blood Group AB** has both A and B antigens.
- **Blood Group O** has no A or B antigens.

### Step 3: Understand Antiserum
Antiserum contains antibodies that can react with specific antigens.
- **Anti-A antiserum** will clump blood with A antigens.
- **Anti-B antiserum** will clump blood with B antigens.

### Step 4: Analyze the Options
We need to determine which blood group will only clump with anti-B antiserum:
1. **AB**: This group has both A and B antigens, so it would clump with both anti-A and anti-B.
2. **B**: This group has only B antigens, so it will clump with anti-B but not with anti-A.
3. **AB and B**: This option includes AB, which we already established clumps with both antisera.
4. **O**: This group has no antigens, so it will not clump with either antiserum.

### Step 5: Conclusion
The only blood group that forms a clump with only anti-B antiserum is **Blood Group B**.

### Final Answer
The correct answer is **Option 2: B**.

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