Assertion : Histones are acidic proteins .
Reason : Cellobiose is an example of disaccharide.

Options

A. (a) If both assertion and Reason are true and the Reason is the correct explanation of the assertion .
B. (b) If both Assertion and Reason ate true , but the reason is not the correct explanation of the assertion .
C. (c) If Assertion is true , but Reason is false
D. (d) if both Assertion and Reason are false.

Answer

To solve the assertion-reason question, we will analyze both the assertion and the reason step by step.

### Step 1: Analyze the Assertion
- **Assertion**: Histones are acidic proteins.
- Histones are proteins that play a crucial role in packaging DNA in the nucleus of eukaryotic cells. They are known to be positively charged due to the presence of basic amino acids like lysine and arginine.
- Since DNA is negatively charged, histones bind to DNA to help condense it into a compact structure known as chromatin.
- Therefore, the assertion that histones are acidic proteins is **false**. Histones are actually classified as basic proteins.

### Step 2: Analyze the Reason
- **Reason**: Cellobiose is an example of a disaccharide.
- Cellobiose is indeed a disaccharide composed of two glucose molecules linked together by a glycosidic bond.
- This statement is **true** as it correctly identifies cellobiose as a disaccharide.

### Step 3: Determine the Relationship
- The assertion is false, and the reason is true. However, the reason does not explain the assertion. They are unrelated statements.

### Conclusion
Based on the analysis:
- The assertion is false, and the reason is true, but they do not explain each other.
- Therefore, the correct answer is option D: "If both assertion and reason are false."

### Final Answer
The answer is D: Both assertion and reason are false.

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