Assertion (A) Periplaneta americana is nocturnal, omnivorous, household pest.
Reason (R) It is because it acts as scavenger.

Options

A. A is true, but R is false
B. A is false, but R is true
C. Both A and R are true and R is correct explanation of A
D. Both A and R are true, but R is not correct explanation of A

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion (A)**: The assertion states that "Periplaneta americana is nocturnal, omnivorous, and a household pest."
- **Nocturnal**: This means that the cockroach is active during the night.
- **Omnivorous**: This indicates that it can eat a variety of foods, including both plant and animal matter.
- **Household Pest**: This implies that it is commonly found in homes and can cause problems, such as spreading diseases.

2. **Evaluating the Reason (R)**: The reason states that "It is because it acts as a scavenger."
- **Scavenger**: A scavenger is an organism that feeds on dead or decaying organic matter. Cockroaches are known to feed on waste materials, which aligns with this definition.

3. **Determining the Truth of A and R**:
- **Is A True?**: Yes, Periplaneta americana is indeed nocturnal, omnivorous, and recognized as a household pest.
- **Is R True?**: Yes, it is also true that cockroaches act as scavengers by feeding on decaying matter.

4. **Analyzing the Relationship Between A and R**:
- While both statements are true, the reason (R) does not adequately explain the assertion (A). The assertion describes the characteristics of Periplaneta americana, while the reason provides additional information about its feeding habits but does not directly explain why it is classified as nocturnal, omnivorous, and a household pest.

5. **Conclusion**:
- Both A and R are true, but R is not the correct explanation of A. Therefore, the correct answer is: "Both A and R are true, but R is not the correct explanation of A."

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