Assertion: Photosynthetically `C_(4)` plants are less efficient than `C_(3)` plants.
Reason: The operation of `C_(4)` pathway requires the involvement of only bundle-sheath cells.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion.
B. It both Assertion & Reason are true but the reason is not the correct explanation of the assertion.
C. If Assertion is true statement but Reason is false.
D. It both Assertion and Reason are false statements.

Explanation

To solve the given question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Photosynthetically C4 plants are less efficient than C3 plants."
- This statement is generally considered false. C4 plants are typically more efficient than C3 plants, especially in conditions of low carbon dioxide concentration and high temperatures.

2. **Understanding the Reason**:
- The reason states that "The operation of C4 pathway requires the involvement of only bundle-sheath cells."
- This statement is also false. The C4 pathway involves both mesophyll cells and bundle-sheath cells. In mesophyll cells, carbon dioxide is initially fixed, and then the Calvin cycle occurs in the bundle-sheath cells.

3. **Evaluating the Truth of Both Statements**:
- Since both the assertion and the reason are false, we can conclude that neither statement accurately represents the facts about C3 and C4 plants.

4. **Choosing the Correct Option**:
- Given that both the assertion and reason are false, the correct option is the one that states "if both assertion and reason are false statements."

### Final Answer:
The correct option is **4**: Both assertion and reason are false statements.

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