The site of production of ADA in the body is

Options

A. erythrocytes
B. lymphocytes
C. blood plasma
D. osteocytes

Explanation

To determine the site of production of ADA (adenosine deaminase) in the body, we can follow these steps:

1. **Understand ADA**: Recognize that ADA is an enzyme that plays a crucial role in the immune system. It is involved in the metabolism of adenosine, which is important for the functioning of lymphocytes.

2. **Identify the Cells Involved**: Know that lymphocytes are a type of white blood cell (WBC) that are essential for the immune response. They are produced in the bone marrow.

3. **Consider the Options**: The question provides several options:
- Erythrocytes (red blood cells)
- Lymphocytes (white blood cells)
- Blood plasma
- Osteocytes (bone cells)

4. **Eliminate Incorrect Options**:
- Erythrocytes are responsible for oxygen transport and do not produce ADA.
- Blood plasma is the liquid component of blood and does not produce enzymes.
- Osteocytes are involved in bone maintenance and do not produce ADA.

5. **Select the Correct Answer**: Since lymphocytes are the white blood cells that produce ADA, the correct answer is lymphocytes.

**Final Answer**: The site of production of ADA in the body is lymphocytes.

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