Due to the active role in phagocytosis, neutrophils are called  

Options

A. microscopic policemen
B. internal scavenger
C. body guards
D. none

Answer

**Step-by-Step Solution:**

1. **Understanding Phagocytosis**: Phagocytosis is the process by which certain cells, known as phagocytes, engulf and digest solid particles, such as bacteria and dead cell debris. This is an essential part of the immune response.

2. **Identifying Neutrophils**: Neutrophils are a type of white blood cell that play a crucial role in the immune system. They are one of the first responders to sites of infection and are highly effective at engulfing and destroying pathogens.

3. **Analyzing the Options**: The question provides four options:
- Microscopic policemen
- Internal scavengers
- Bodyguards
- None

4. **Evaluating the Role of Neutrophils**: Given their active role in phagocytosis, neutrophils can be likened to "policemen" because they patrol the body for pathogens and eliminate them, similar to how policemen maintain law and order.

5. **Selecting the Correct Answer**: Among the options, "microscopic policemen" is the most appropriate term to describe neutrophils due to their microscopic size and their role in fighting infections.

6. **Conclusion**: Therefore, the correct answer is that neutrophils are called "microscopic policemen" due to their active role in phagocytosis.

**Final Answer**: Microscopic policemen.

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