Transpiration is high under

Options

A. Dry environment
B. Low atmospheric pressure
C. High temperature
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Transpiration**: Transpiration is the process by which water vapor is lost from the aerial parts of plants, primarily through small openings called stomata. The rate of transpiration can be influenced by various environmental factors.

2. **Analyzing Dry Environment**: In a dry environment, the humidity is low. This creates a higher gradient between the moisture inside the plant and the dry air outside, leading to an increase in the rate of transpiration. Therefore, option (a) is correct.

3. **Considering Low Atmospheric Pressure**: When the atmospheric pressure is low, the water vapor concentration in the air is also lower. This encourages more water to evaporate from the plant into the atmosphere, thus increasing transpiration. Hence, option (b) is also correct.

4. **Evaluating High Temperature**: High temperatures increase the kinetic energy of water molecules, causing them to evaporate more quickly. This results in a higher rate of transpiration as well. Therefore, option (c) is correct.

5. **Conclusion**: Since all three conditions (dry environment, low atmospheric pressure, and high temperature) contribute to an increase in the rate of transpiration, the correct answer is option (d) – all of the above.

**Final Answer**: D. All of the above.

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