Assertion : The difference in shapes of leaves produced in air and those produced in water in buttercup represent the heterophyllous development due to environment.
Reason : The phenomenon of heterophylly is an example of plasticity.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false

Explanation

To solve the question, we need to analyze both the assertion and the reason provided, and determine their correctness and relationship.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that the difference in shapes of leaves produced in air and those produced in water in buttercup represents heterophyllous development due to the environment.
- Heterophylly refers to the phenomenon where a single plant produces different types of leaves in response to varying environmental conditions. In the case of buttercup, the leaves submerged in water are typically different in shape compared to those exposed to air.

2. **Understanding the Reason**:
- The reason states that the phenomenon of heterophylly is an example of plasticity.
- Plasticity in plants refers to their ability to adapt their growth and form in response to environmental conditions. Heterophylly can be seen as a form of plasticity since it involves changes in leaf morphology based on environmental factors.

3. **Evaluating the Correctness**:
- Both the assertion and the reason are correct. The assertion accurately describes heterophylly in buttercup plants, and the reason correctly identifies heterophylly as an example of plasticity.

4. **Assessing the Relationship**:
- While both statements are correct, the reason does not fully explain the assertion. Heterophylly is indeed a result of environmental adaptation (plasticity), but the assertion specifically addresses the morphological differences in leaves due to water and air conditions, which is a more specific aspect of plant adaptation.

5. **Conclusion**:
- The correct answer is that both the assertion and the reason are correct, but the reason is not the correct explanation for the assertion. Therefore, the answer is option B: Assertion is correct, Reason is correct, but Reason is not the correct explanation.