A person with blood group A has

Options

A. antigen A and antibody b
B. antigen B and antibody a
C. both antibodies
D. no antibody and no antigen

Explanation

To solve the question regarding a person with blood group A, we need to understand the characteristics of blood groups in the ABO blood group system. Here’s a step-by-step solution:

### Step 1: Understand Blood Group A Characteristics
- Blood group A individuals have **A antigens** on the surface of their red blood cells. This is a key characteristic that defines their blood group.

### Step 2: Identify the Antibodies Present
- People with blood group A produce **anti-B antibodies** in their plasma. These antibodies will react against any B antigens that may be introduced into their system.

### Step 3: Confirm the Absence of Anti-A Antibodies
- Since blood group A has A antigens, they do not produce **anti-A antibodies**. If they did, it would cause their immune system to attack their own red blood cells.

### Step 4: Conclusion
- Therefore, a person with blood group A has **A antigens** and **anti-B antibodies** in their blood.

### Final Answer
A person with blood group A has **antigen A** and **antibody B**.

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