Which one is exclusive xerophytic adaptation ?

Options

A. (a) Absence of stomata
B. (b) Long tap root system
C. (c) Stipular leaves
D. (d) Spines

Answer

### Step-by-Step Solution:

1. **Understanding Xerophytes**: Xerophytes are plants that are adapted to survive in environments with very low water availability. They have developed various adaptations to minimize water loss and maximize water retention.

2. **Analyzing the Options**: The question asks for an exclusive adaptation of xerophytes. We need to evaluate each option provided to determine which one is unique to xerophytes.

3. **Option A - Absence of Stomata**: This option suggests that xerophytes have no stomata. This is incorrect because xerophytes do have stomata, although they are fewer in number and often located in sunken pits to reduce water loss.

4. **Option B - Long Tap Root System**: This option states that xerophytes have a long tap root system. While many xerophytes do have deep roots to access water, this adaptation is not exclusive to xerophytes as many other plants also exhibit this trait.

5. **Option C - Stipular Leaves**: This option refers to stipular leaves, which can be modified into spines or tendrils. However, this is not an exclusive adaptation of xerophytes, as other plant types can also have stipular leaves.

6. **Option D - Spines**: This option indicates that xerophytes have spines as a modification of their leaves. This adaptation is unique to xerophytes as spines help reduce water loss through transpiration and provide protection from herbivores.

7. **Conclusion**: After evaluating all the options, the exclusive xerophytic adaptation is the presence of spines, which serve to minimize water loss and protect the plant.

### Final Answer:
The exclusive xerophytic adaptation is **spines**.

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