The middle man of the body is

Options

A. Blood
B. Plasma
C. Lymph
D. Serum

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the "middle man of the body." This implies a substance or fluid that plays a crucial intermediary role in the body's physiological processes.

2. **Identifying the Options**: The options provided are blood, lymph, plasma, and serum. We need to evaluate which of these serves as a middleman in the transport and exchange of materials in the body.

3. **Analyzing Each Option**:
- **Blood**: Blood is a vital fluid that transports various substances throughout the body, including oxygen, nutrients, and waste products. However, it is not specifically termed as a "middleman" since it serves a broader role in systemic circulation.
- **Lymph**: Lymph is a clear fluid that circulates through the lymphatic system. It is responsible for transporting materials between the blood and body tissues, including oxygen, nutrients, hormones, and metabolic waste. This exchange function makes lymph the most suitable candidate for the "middleman" role.
- **Plasma**: Plasma is the liquid component of blood that remains after the cellular components (RBCs, WBCs, and platelets) are removed. While it plays an important role in transporting substances, it is part of blood rather than an intermediary fluid.
- **Serum**: Serum is similar to plasma but lacks clotting factors and cellular components. It is not primarily involved in the exchange of materials between blood and tissues.

4. **Conclusion**: Based on the analysis, lymph is identified as the correct answer because it specifically facilitates the exchange of materials between blood and body tissues, thus acting as the "middleman."

5. **Final Answer**: The middle man of the body is **lymph**.

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