Antibodies are produced by

Options

A. Lymphocytes
B. Leucocytes
C. Monocytes
D. Spleen

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks about the origin of antibodies in the human body. Antibodies are crucial components of the immune system that help defend against pathogens.

2. **Identify the Options**: The options provided are:
- A) Lymphocytes
- B) Leukocytes
- C) Monocytes
- D) Spleen

3. **Define Key Terms**:
- **Lymphocytes**: A type of white blood cell that plays a significant role in the immune response. They are further divided into B cells and T cells.
- **Leukocytes**: A broad category of white blood cells that includes lymphocytes, monocytes, and others.
- **Monocytes**: A type of leukocyte that can differentiate into macrophages and dendritic cells but does not produce antibodies.
- **Spleen**: An organ that filters blood and helps in immune responses but does not directly produce antibodies.

4. **Determine the Correct Answer**:
- Antibodies are specifically produced by **B lymphocytes** (a type of lymphocyte). When B lymphocytes are activated, they differentiate into plasma cells, which are responsible for producing antibodies.
- Therefore, the correct answer is **A) Lymphocytes**.

5. **Eliminate Incorrect Options**:
- **B) Leukocytes**: While leukocytes include lymphocytes, they are not specifically responsible for antibody production.
- **C) Monocytes**: These cells do not produce antibodies.
- **D) Spleen**: The spleen supports immune functions but does not produce antibodies directly.

6. **Conclusion**: The antibodies are produced by lymphocytes, specifically by B lymphocytes which differentiate into plasma cells to produce antibodies.

**Final Answer**: Antibodies are produced by **lymphocytes**.

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