For higher plants, flowers are chiefly used as a basis of classification, because :–

Options

A. These show a great variety in colour
B. It can be preserved eaisly
C. Reproductive parts are more conservative than vegetative parts
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Role of Flowers in Classification:**
- Flowers are crucial for the classification of higher plants because they are involved in reproduction. The structure and arrangement of flowers can provide significant insights into the relationships between different plant species.

2. **Evaluating the Options:**
- The question presents four options regarding why flowers are chiefly used for classification:
- Option 1: Flowers show great variety in colors.
- Option 2: Flowers are easily preserved.
- Option 3: Reproductive parts are more conservative than vegetative parts.
- Option 4: None of these.

3. **Analyzing Option 1:**
- While flowers do exhibit a wide range of colors, this characteristic is not stable enough for classification. The color can vary significantly within a species due to environmental factors, making it unreliable as a classification criterion.

4. **Analyzing Option 2:**
- Flowers are not easily preserved compared to other plant parts like leaves or stems. Leaves and stems contain sclerenchymatous tissues that allow them to be preserved for longer periods, while flowers are more delicate and do not have such structures.

5. **Analyzing Option 3:**
- The reproductive parts of plants (flowers) are generally more conservative than vegetative parts. This means that the characteristics of flowers tend to remain more constant over time compared to leaves and stems, which can change more rapidly due to evolutionary pressures.

6. **Conclusion:**
- Based on the analysis, the most valid reason for using flowers as a basis for classification in higher plants is that the reproductive parts are more conservative than the vegetative parts. Therefore, the correct answer is Option 3.

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