Blood group Antigen are `:-`

Options

A. Found in Hb molecule
B. Found in Plasma protein
C. Found on RBC
D. None

Answer

**Step-by-Step Solution:**

1. **Understanding Blood Group Antigens:**
- Blood group antigens are specific molecules present on the surface of red blood cells (RBCs). They play a crucial role in determining an individual's blood type.

2. **Identifying Types of Blood Group Antigens:**
- There are different blood groups based on the presence of specific antigens:
- **Type A:** Has A antigens on the surface of RBCs.
- **Type B:** Has B antigens on the surface of RBCs.
- **Type AB:** Has both A and B antigens on the surface of RBCs.
- **Type O:** Has no A or B antigens on the surface of RBCs.

3. **Role of Antigens and Antibodies:**
- Along with antigens, blood also contains antibodies. Antibodies are proteins found in plasma that react against antigens not present on the individual's own RBCs.
- For example, Type A blood has A antigens and anti-B antibodies.

4. **Locating Blood Group Antigens:**
- Blood group antigens are specifically located on the membranes of red blood cells (RBCs), also known as erythrocytes.

5. **Evaluating the Options:**
- **Option A:** Hemoglobin - Incorrect, as hemoglobin is a protein that carries oxygen and does not contain blood group antigens.
- **Option B:** Plasma protein - Incorrect, as plasma proteins do not contain blood group antigens; they contain antibodies.
- **Option C:** RBC (Red Blood Cells) - Correct, as blood group antigens are found on the surface of RBCs.
- **Option D:** None - Incorrect, since option C is the correct answer.

6. **Conclusion:**
- The correct answer to the question "Blood group antigens are found in" is **Option C: found on RBCs.**

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