$ Leaves of monocots are amphistomatic.
! Dicot leaf has dimophic cells in mesophyll.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To solve the question regarding the statements about monocot and dicot leaves, we will analyze each statement step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "leaves of monocots are amphistomatic."
- **Definition**: Amphistomatic means that the leaves have stomata on both the upper and lower surfaces.
- **Monocots**: These are a group of flowering plants characterized by having one cotyledon in their seeds. Examples include grasses, lilies, and orchids.
- **Conclusion**: Since monocot leaves do indeed have stomata on both sides, this statement is **True**.

2. **Understanding the Reasoning**:
- The reasoning states that "dicot leaves have dimorphic cells in mesophyll."
- **Definition**: Dimorphic cells refer to the presence of two different types of cells within the mesophyll tissue of leaves.
- **Dicots**: These are another group of flowering plants characterized by having two cotyledons in their seeds. Examples include beans, roses, and sunflowers.
- **Mesophyll**: This is the inner tissue of the leaf where photosynthesis occurs, typically consisting of palisade and spongy mesophyll cells.
- **Conclusion**: Dicot leaves do have dimorphic cells in their mesophyll, making this statement also **True**.

3. **Analyzing the Relationship**:
- Now, we need to determine if the reasoning provided is the correct explanation for the assertion.
- The assertion is about the stomatal arrangement in monocots, while the reasoning discusses the cell types in dicots.
- **Conclusion**: Although both statements are true, the reasoning does not explain the assertion about monocots. Therefore, the reasoning is not the correct explanation for the assertion.

4. **Final Answer**:
- Both the assertion and the reasoning are true, but the reasoning is not the correct explanation for the assertion.

### Summary:
- **Assertion**: True (Monocots are amphistomatic)
- **Reasoning**: True (Dicots have dimorphic mesophyll cells)
- **Conclusion**: Reasoning is not the correct explanation for the assertion.

### Answer Choice:
- The correct choice is that both the assertion and reasoning are true, but the reasoning is not the correct explanation for the assertion.

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