Assertion (A): Deoxyribose, `C_5 H_(10)O_(4)` is not a carbohydrate. Reason (R): Carbohydrates are optically active polyhydroxy aldehyde or polyhydroxy ketone or substances which give aldehyde or ketone on hydrolysis.

Options

A. Both A and Rare true and R is the correct explanation of A
B. Both A and R are true but R is NOT the correct explanation of A
C. A is true but R is false
D. A is false and R is True

Explanation

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

### Step 1: Analyze the Assertion (A)
The assertion states: "Deoxyribose, C₅H₁₀O₄ is not a carbohydrate."

- **Understanding Deoxyribose**: Deoxyribose is a sugar that is a component of DNA. It is classified as a carbohydrate because it is a sugar molecule.
- **Chemical Composition**: The formula C₅H₁₀O₄ indicates that it has multiple hydroxyl (OH) groups, which is characteristic of carbohydrates.

**Conclusion**: The assertion is **false** because deoxyribose is indeed a carbohydrate.

### Step 2: Analyze the Reason (R)
The reason states: "Carbohydrates are optically active polyhydroxy aldehyde or polyhydroxy ketone or substances which give aldehyde or ketone on hydrolysis."

- **Definition of Carbohydrates**: This definition is correct. Carbohydrates can be classified as polyhydroxy aldehydes (like glucose) or polyhydroxy ketones (like fructose). They also can yield aldehyde or ketone groups upon hydrolysis.
- **Optical Activity**: Many carbohydrates are optically active due to the presence of chiral centers.

**Conclusion**: The reason is **true** as it accurately describes carbohydrates.

### Step 3: Determine the Relationship Between A and R
- The assertion (A) is false, while the reason (R) is true.
- Since the reason does not explain the assertion (because the assertion is incorrect), we conclude that the statements are not related in a way that the reason supports the assertion.

### Final Conclusion
- **Assertion (A)**: False
- **Reason (R)**: True
- Therefore, the correct answer is that A is false, but R is true.

### Answer: Option 4: A is false but R is true.

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