[A]: Phagocyte cells digest microbes.
[R]: Killer cells destroy virus infected cells and tumor cells.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

To solve the question regarding the assertion and reason statements about phagocyte cells and killer cells, let's break it down step by step.

### Step-by-Step Solution:

1. **Identify the Assertion and Reason**:
- **Assertion (A)**: Phagocyte cells digest microbes.
- **Reason (R)**: Killer cells destroy virus-infected cells and tumor cells.

2. **Evaluate the Assertion**:
- Phagocyte cells are a type of white blood cell (WBC) that play a crucial role in the immune system by engulfing and digesting pathogens, such as bacteria and other microbes. This process is known as phagocytosis.
- Therefore, the assertion is **true**.

3. **Evaluate the Reason**:
- Killer cells, also known as natural killer (NK) cells, are a type of cytotoxic lymphocyte that is essential for the innate immune response. They target and destroy virus-infected cells and tumor cells.
- Hence, the reason is also **true**.

4. **Determine the Relationship**:
- The assertion discusses the function of phagocyte cells, while the reason discusses the function of killer cells.
- Although both statements are true, the reason does not explain the assertion. They refer to different types of immune responses and cells.

5. **Conclusion**:
- Since both the assertion and reason are true but the reason does not provide a correct explanation for the assertion, the correct answer is that both are true, but the reason is not the correct explanation of the assertion.

### Final Answer:
Both assertion and reason are true, but reason is not the correct explanation of assertion.

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