Which of the following statements is incorrect

Options

A. A person of 'O' blood group has anti 'A' and anti 'B' antibodies in his blood plasma
B. A person of 'B' blood group can't donate blood to a person of 'A' blood group
C. Blood group is designated on the basis of the presence of antibodies in the blood plasma
D. A person of AB blood group is universal recipient

Explanation

To determine which statement is incorrect regarding blood groups, we will analyze each option provided in the question step by step.

**Step 1: Analyze Statement A**
- Statement: "A person of O blood group has NTA and NTB antibodies in his blood plasma."
- Analysis: The O blood group does indeed have both anti-A (NTA) and anti-B (NTB) antibodies in the plasma. Therefore, this statement is correct.

**Step 2: Analyze Statement B**
- Statement: "A person of B blood group can't donate blood to a person of A blood group."
- Analysis: A person with B blood can donate blood to a person with A blood group, as the recipient's immune system will not react against the B antigens present in the donor's blood. Thus, this statement is also correct.

**Step 3: Analyze Statement C**
- Statement: "Blood group is designated on the basis of presence of antibodies in the blood plasma."
- Analysis: This statement is incorrect. Blood groups are designated based on the presence of antigens on the surface of red blood cells, not antibodies in the plasma. Therefore, this statement is the incorrect one.

**Step 4: Analyze Statement D**
- Statement: "A person of AB blood group is a universal recipient."
- Analysis: This statement is correct. Individuals with AB blood group can receive blood from any blood group (A, B, AB, or O) without experiencing an immune reaction, making them universal recipients.

**Conclusion:**
- The incorrect statement is **Statement C**: "Blood group is designated on the basis of presence of antibodies in the blood plasma."

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