Natural killer cells are type of-

Options

A. Monocytes
B. Lymphocytes
C. Neutrophils
D. Phagocytes

Answer

To determine what type of cells natural killer cells are, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Natural Killer Cells**:
- Natural killer (NK) cells are a type of immune cell that play a crucial role in the body's defense against tumors and virally infected cells.

2. **Identifying the Categories**:
- The question provides four options: monocytes, lymphocytes, neutrophils, and phagocytes. We need to identify which category NK cells belong to.

3. **Reviewing the Options**:
- **Monocytes**: These are a type of white blood cell that differentiate into macrophages and dendritic cells. They are not NK cells.
- **Lymphocytes**: This category includes T cells, B cells, and natural killer cells.
- **Neutrophils**: These are polymorphonuclear leukocytes that primarily respond to bacterial infections. They are not NK cells.
- **Phagocytes**: This term refers to cells that engulf and digest pathogens, including macrophages and neutrophils, but does not include NK cells.

4. **Conclusion**:
- Since natural killer cells are involved in the immune response and are classified under lymphocytes, the correct answer is that natural killer cells are a type of **lymphocyte**.

### Final Answer:
Natural killer cells are a type of **lymphocyte**.

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