Organisms are absent in their zone of

Options

A. Stress
B. Intolerance
C. Optimum tolerance.
D. Both A and B.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks in which zone organisms are absent. This implies we are looking for a specific condition or environment where organisms cannot survive.

2. **Analyzing the Options**: We have four options to consider:
- A) Stress
- B) Intolerance
- C) Optimum tolerance
- D) None of the above

3. **Evaluating Option A (Stress)**: In a zone of stress, organisms may experience challenges, but they often adapt or respond to these stresses (e.g., through hormonal changes). Therefore, organisms are not absent in this zone.

4. **Evaluating Option B (Intolerance)**: The term "intolerance" suggests that this is a zone where organisms cannot survive due to extreme conditions (e.g., temperature, pH, etc.). Hence, organisms are indeed absent in their zone of intolerance.

5. **Evaluating Option C (Optimum Tolerance)**: In the zone of optimum tolerance, organisms thrive because conditions are favorable. Thus, organisms are present in this zone.

6. **Conclusion**: Based on the evaluations, the correct answer is that organisms are absent in their zone of **intolerance** (Option B).

**Final Answer**: Organisms are absent in their zone of **intolerance**.

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