The blood cell that is a precursor to microglial cell is –

Options

A. A basophil
B. A monocyte
C. A neutrophil
D. A lymphocyte

Answer

To answer the question, "The blood cell that is a precursor to microglial cell is –", we can follow these steps:

### Step-by-Step Solution

1. **Identify Microglial Cells**: Microglial cells are a type of neuroglial cell found in the brain and spinal cord. They play a crucial role in the immune defense mechanism of the central nervous system (CNS).

2. **Understand the Function of Microglial Cells**: These cells act as specialized macrophages, which means they are involved in the phagocytosis of pathogens and debris in the CNS, helping to maintain the health of the neural environment.

3. **Determine the Origin of Microglial Cells**: Microglial cells originate from blood cells. Specifically, they are derived from a type of white blood cell (WBC) known as monocytes.

4. **Evaluate the Options Given**: The options provided are:
- Basophil
- Monocyte
- Neutrophil
- Lymphocyte

5. **Select the Correct Answer**: Since microglial cells are derived from monocytes, the correct answer is **monocyte**.

### Final Answer
The blood cell that is a precursor to microglial cell is **monocyte**.

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