A hexose sugar is

Options

A. Arabinose
B. Galactose
C. Mannose
D. Both B and C.

Answer

To determine which of the given sugars is a hexose sugar, we need to analyze the carbon content of each option. Hexose sugars are defined as monosaccharides that contain six carbon atoms. Let's go through the options step by step.

### Step 1: Understand the definition of hexose sugar
Hexose sugars are monosaccharides that contain six carbon atoms. The general formula for monosaccharides is \( C_nH_{2n}O_n \), where \( n \) is the number of carbon atoms.

### Step 2: Analyze the given options
1. **Arabinose**:
- Arabinose is a five-carbon sugar (pentose).
- Therefore, it is **not** a hexose sugar.

2. **Galactose**:
- Galactose has six carbon atoms.
- Thus, it **is** a hexose sugar.

3. **Mannose**:
- Mannose also has six carbon atoms.
- Therefore, it **is** a hexose sugar as well.

4. **Both B and C**:
- Since both galactose and mannose are hexose sugars, this option is valid.

### Step 3: Conclusion
Based on the analysis:
- Arabinose is not a hexose.
- Galactose and Mannose are both hexoses.
- Therefore, the correct answer is **both B (Galactose) and C (Mannose)**.

### Final Answer:
The correct answer is **Option 4: Both B and C**.

---