Antiserum is rich in

Options

A. steroids
B. antibodies
C. antigens
D. RBCs

Answer

### Step-by-Step Solution:

1. **Understanding Antiserum**: Antiserum is a blood serum that contains specific antibodies. It is produced in response to an antigen, which is a foreign substance that triggers an immune response.

2. **Identifying the Components of Antiserum**: The primary components of antiserum are antibodies. These antibodies can be classified into two types: monoclonal antibodies and polyclonal antibodies.

3. **Role of Antibodies**: Antibodies are proteins produced by B cells (a type of white blood cell) that help the immune system identify and neutralize pathogens such as bacteria and viruses.

4. **Passive Immunity**: Antiserum provides passive immunity, which means it offers immediate protection by supplying ready-made antibodies rather than requiring the body to produce them in response to an infection.

5. **Conclusion**: Since antiserum is specifically rich in antibodies, the correct answer to the question "Antiserum is rich in" is "antibodies."

### Final Answer:
Antiserum is rich in antibodies.

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