Assertion : sucrose is known as invert sugar
Reason : sucrose is a disaccharide

Options

A. If both assertion & Reason are true & the Reason is a correct explanation of the Assertion
B. If both Assertion & Reason ar True but Reason is not a correct explantation of the Assertion
C. If Assertion is True but the Reason is False
D. If both Assertion & Reason are false

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "sucrose is known as invert sugar." This is true. Invert sugar refers to a mixture of glucose and fructose, which results from the hydrolysis of sucrose. When sucrose is hydrolyzed, it changes from a dextrorotatory (right-rotating) sugar to a levorotatory (left-rotating) mixture, hence the term "invert."

2. **Understanding the Reason**: The reason states that "sucrose is a disaccharide." This is also true. Sucrose is composed of two monosaccharides: glucose and fructose. Therefore, it qualifies as a disaccharide.

3. **Analyzing the Relationship**: While both the assertion and the reason are true, the reason does not adequately explain why sucrose is called invert sugar. The term "invert sugar" specifically relates to the change in optical rotation upon hydrolysis, rather than the fact that sucrose is a disaccharide.

4. **Conclusion**: Since both statements are true but the reason does not correctly explain the assertion, the correct conclusion is that the assertion is true, the reason is true, but the reason is not a correct explanation of the assertion.

### Final Answer:
The correct answer is: Both the assertion and the reason are true, but the reason is not a correct explanation of the assertion.

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