Under unfavourable conditions many zooplankton species in lakes and ponds enter

Options

A. Dormancy
B. Hibernation
C. Diapause
D. Menopause

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the behavior of zooplankton species in lakes and ponds under unfavorable conditions. We need to identify the correct term that describes this behavior from the given options.

2. **Analyzing the Options**:
- **Dormancy**: This is a general term for a state where metabolic activities are reduced in response to unfavorable conditions. It can include various forms of inactivity.
- **Hibernation**: This specifically refers to a type of dormancy that occurs in some animals during winter, where metabolic rates are significantly lowered to conserve energy.
- **Diapause**: This is a specific type of dormancy, particularly in insects, where growth and development are suspended during unfavorable environmental conditions.
- **Menopause**: This term refers to the cessation of menstrual cycles in females and is not applicable to zooplankton.

3. **Identifying the Correct Answer**: Since the question pertains to zooplankton, which are aquatic organisms, and given that they enter a state where growth and development are suspended under unfavorable conditions, the most appropriate term is **diapause**.

4. **Conclusion**: Therefore, the correct answer to the question is **C. Diapause**.

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