In aquatic plant Ranunculus flabellair (buttercup), submerged leaves are highly dissected whereas the emerged leaves are broad and lobed. This is an example of

Options

A. heterophylly
B. enviornmental plasticity
C. phenology
D. both (a) and (b)

Explanation

To solve the question regarding the aquatic plant Ranunculus flabellaris (buttercup) and the nature of its submerged and emerged leaves, we can break down the concepts involved step by step.

### Step-by-Step Solution:

1. **Understanding the Plant's Characteristics**:
- The Ranunculus flabellaris exhibits two distinct types of leaves: highly dissected submerged leaves and broad lobed emerged leaves.
- This variation in leaf morphology is a response to different environmental conditions (submerged vs. emerged).

2. **Defining Key Terms**:
- **Heterophylly**: This refers to the phenomenon where a single plant produces different types of leaves at different stages of growth or under different environmental conditions. In this case, the buttercup has two types of leaves depending on whether it is submerged in water or emerged above the water.
- **Environmental Plasticity**: This is the ability of an organism to change its morphology or physiology in response to environmental changes. Heterophylly is a specific example of environmental plasticity.

3. **Analyzing the Options**:
- The question provides four options:
- A) Heterophily
- B) Environmental Plasticity
- C) Phenology
- D) Both A and B
- Since the plant exhibits heterophylly (different leaf types) and this is a form of environmental plasticity, we can conclude that both A and B are correct.

4. **Eliminating Incorrect Options**:
- **Phenology** is the study of seasonal natural phenomena and does not directly relate to the morphological changes of leaves in response to environmental conditions. Therefore, it is not applicable in this context.

5. **Final Conclusion**:
- The correct answer to the question is option D: Both A (Heterophily) and B (Environmental Plasticity).

### Final Answer:
The phenomenon observed in Ranunculus flabellaris, where submerged leaves are highly dissected and emerged leaves are broad and lobed, is an example of both heterophily and environmental plasticity. Thus, the correct answer is option D: Both A and B.

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