Assertion `:-` Blood group 'O' is a univesal donar blood.
Reason `:-` Antiboidies of blood group are absent in blood group 'O'.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion .
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding Blood Groups**: There are four main blood groups: A, B, AB, and O. These groups are determined by the presence or absence of specific antigens on the surface of red blood cells.

2. **Identifying Blood Group O**: Blood group O is unique because it does not have A or B antigens on the surface of its red blood cells. Instead, it has both anti-A and anti-B antibodies in the plasma.

3. **Assertion Evaluation**: The assertion states that blood group O is a universal donor. This is true because individuals with blood group O can donate blood to anyone without causing an immune reaction, as there are no antigens present that could trigger an immune response in the recipient.

4. **Reason Evaluation**: The reason provided states that antibodies of blood group O are absent. This is incorrect. While blood group O does not have A or B antigens, it does contain both anti-A and anti-B antibodies.

5. **Conclusion**: Therefore, the assertion is true (blood group O is a universal donor), but the reason is false (antibodies are present in blood group O).

6. **Final Answer**: The correct answer is that the assertion is true, but the reason is false.

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