Which of the following pairs represents anomers ?

Options

A.
B.
C.
D.

Explanation

To determine which pairs represent anomers, we need to understand the definition of anomers and how they relate to carbohydrate chemistry.

### Step-by-Step Solution:

1. **Understanding Anomers**: Anomers are a specific type of stereoisomer found in carbohydrates. They differ in configuration at the anomeric carbon (C1) after the carbohydrate cyclizes. For example, in glucose, the anomers are α-D-glucose and β-D-glucose.

2. **Identifying the Anomeric Carbon**: The anomeric carbon is the carbon that was the carbonyl carbon (C=O) in the open-chain form of the sugar. When the sugar cyclizes, this carbon becomes a new chiral center.

3. **Recognizing the Configuration**: Anomers differ only in the orientation of the hydroxyl group (-OH) attached to the anomeric carbon. If the -OH group is on the opposite side of the CH2OH group (in the Haworth projection), it is referred to as the α-anomer. If it is on the same side, it is the β-anomer.

4. **Analyzing Given Pairs**: To identify which pairs are anomers, we need to look at the structures of the pairs provided in the question. We should check if they differ only at the C1 position.

5. **Conclusion**: After analyzing the pairs, we can conclude which ones are anomers based on the configuration of the hydroxyl group at the anomeric carbon.

### Example of Anomeric Pairs:
- α-D-glucose and β-D-glucose
- α-D-fructose and β-D-fructose