Which one of the following pairs of structures is correctly matched with their correct description

Options

A. leaf thorns-- protection from grazers
B. spines-- reduce transpiration
C. tendrils in pea-- stem modification
D. onion - edible root

Answer

To solve the question, we need to analyze each pair of structures and their descriptions to determine which one is correctly matched.

### Step-by-Step Solution:

1. **Identify the Structures and Descriptions**:
We have four pairs to evaluate:
- Pair 1: Leaf thorns
- Pair 2: Spines
- Pair 3: Tendrils in pea
- Pair 4: Onion

2. **Evaluate Pair 1 (Leaf Thorns)**:
- Description: Modifications of leaves that provide protection from grazers.
- Analysis: Leaf thorns indeed serve as a protective mechanism against herbivores. This description is correct.

3. **Evaluate Pair 2 (Spines)**:
- Description: Adaptation to reduce transpiration.
- Analysis: Spines are modified leaves that help reduce water loss in plants, especially in arid regions. This description is also correct.

4. **Evaluate Pair 3 (Tendrils in Pea)**:
- Description: Stem modification.
- Analysis: Tendrils in pea plants are actually modifications of leaves, not stems. Therefore, this description is incorrect.

5. **Evaluate Pair 4 (Onion)**:
- Description: Edible root.
- Analysis: The edible part of the onion is the fleshy leaves, not the roots. Thus, this description is also incorrect.

6. **Conclusion**:
- From the analysis, we find that Pair 1 (Leaf thorns) and Pair 2 (Spines) are correctly matched with their descriptions. However, since the question asks for a single correct pair, Pair 2 (Spines) is the better option as it specifically addresses the adaptation to reduce transpiration.

### Final Answer:
The correct pair of structures matched with their description is: **Spines - Adaptation to reduce transpiration**.

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