Which of the following sign indicate that the sugar is actually 'dextrorotatory'

Options

A. `-`
B. `+`
C. R-
D. All of these

Answer

To determine which sign indicates that a sugar is dextrorotatory, we need to understand what dextrorotation means in the context of optical activity.

### Step-by-Step Solution:

1. **Understanding Dextrorotation**:
- Dextrorotatory compounds are those that rotate plane-polarized light to the right (clockwise). This property is a characteristic of certain sugars and other optically active substances.

2. **Sign Convention**:
- The rotation of plane-polarized light is measured in degrees and is denoted by a sign. If a compound is dextrorotatory, it is assigned a positive sign (+).

3. **Identifying the Correct Option**:
- Among the options provided, the one that indicates a positive rotation (i.e., +) is the sign that indicates the sugar is dextrorotatory.

4. **Conclusion**:
- Therefore, the correct answer is that the sign indicating the sugar is dextrorotatory is the positive sign (+).

### Final Answer:
The sign that indicates that the sugar is actually dextrorotatory is the positive sign (+).

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