A : Biosynthetic phase of phtosynthesis depend directly on presence of light .
R: Both ATP and NADPH are not essential for assimilation of `CO_(2)` to carbohydrates.

Options

A. If both Assertion % Reson ar true and the reason is the correct explanation of the asserition the mark (1)
B. If both Assertion % Reason are true but the reason, is not the correct explanation of the assertion ,then mark (2)
C. If Assetion is true statement but Reason is false , The mark (3)
D. If both Assertion and Reason are false statements, the mark (4)

Answer

To solve the assertion and reason question, we need to analyze both statements carefully.

### Step 1: Analyze the Assertion
The assertion states: "Biosynthetic phase of photosynthesis depends directly on presence of light."

- The biosynthetic phase, also known as the dark reaction or Calvin cycle, utilizes the products of the light reactions (ATP and NADPH) to convert carbon dioxide into carbohydrates.
- However, this phase does not require light directly; it can occur in the dark as long as the necessary substrates (ATP and NADPH) are available. Therefore, the assertion is **incorrect**.

### Step 2: Analyze the Reason
The reason states: "Both ATP and NADPH are not essential for assimilation of CO₂ to carbohydrates."

- ATP and NADPH are indeed essential for the assimilation of carbon dioxide during the biosynthetic phase. They provide the energy and reducing power necessary for the conversion of CO₂ into glucose.
- Thus, this statement is also **incorrect**.

### Conclusion
Since both the assertion and the reason are incorrect, the correct answer is that both statements are false.

### Final Answer
Both the assertion and the reason are false.

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