The leaves of gymnosperms are well-adapted to withstand extremes of temperature, humidity and wind, because of which of the following features?

Options

A. Needle like leaves
B. Thick cuticle
C. Sunken stomata
D. all of these.

Explanation

To solve the question regarding the adaptation of gymnosperm leaves to withstand extremes of temperature, humidity, and wind, we can break down the features mentioned in the options.

### Step-by-Step Solution:

1. **Understand the Environment**: Gymnosperms often grow in harsh environments where they face extreme temperatures, low humidity, and strong winds. Their leaves must be adapted to survive these conditions.

2. **Analyze the Leaf Structure**:
- **Needle-like Leaves**: Gymnosperms, particularly conifers, have needle-like leaves. This shape reduces the surface area exposed to the elements, which minimizes water loss through transpiration.
- **Thick Cuticle**: The leaves of gymnosperms have a thick cuticle, which is a waxy layer that covers the leaf surface. This cuticle helps to prevent water loss and protects the leaf from extreme environmental conditions.
- **Sunken Stomata**: Gymnosperms also possess sunken stomata. These are openings on the leaf surface that allow for gas exchange but are located deeper within the leaf tissue. This adaptation reduces water loss by limiting exposure to air currents.

3. **Evaluate the Options**:
- **Option 1**: Needle-like leaves - Correct, as they reduce surface area.
- **Option 2**: Thick cuticle - Correct, as it reduces water loss.
- **Option 3**: Sunken stomata - Correct, as they also help in reducing water loss.
- **Option 4**: All of these - Since all the features contribute to the adaptation of gymnosperm leaves, this option is correct.

4. **Conclusion**: The correct answer is option 4, "All of these," as needle-like leaves, thick cuticle, and sunken stomata all play a role in helping gymnosperms withstand extreme environmental conditions.

### Final Answer:
The leaves of gymnosperms are well-adapted to withstand extremes of temperature, humidity, and wind because of **all of these features**: needle-like leaves, thick cuticle, and sunken stomata.

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