Assertion : Glucose is correctly named as D-(+)-glucose. ' 3
Reason : ‘D’ before the name of glucose represents its dextrorotatory nature.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

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

### Step 1: Understand the Assertion
The assertion states that "Glucose is correctly named as D-(+)-glucose."
- This is true. Glucose is indeed referred to as D-(+)-glucose. The "D" indicates the configuration of the molecule based on the orientation of the hydroxyl (OH) group on the asymmetric carbon farthest from the aldehyde or ketone group.

### Step 2: Understand the Reason
The reason states that "‘D’ before the name of glucose represents its dextrorotatory nature."
- This statement is misleading. While D-glucose is dextrorotatory (it rotates plane-polarized light to the right), the "D" in D-glucose does not directly indicate its optical activity. Instead, it refers to the configuration of the molecule. The optical activity is denoted by the "+" sign, which indicates that it is dextrorotatory.

### Step 3: Conclusion
- The assertion is true: Glucose is correctly named as D-(+)-glucose.
- The reason is false: The "D" does not represent dextrorotatory nature; it represents the configuration of the molecule.

### Final Answer
- The assertion is true, and the reason is false.