Ribose is

Options

A. Monosaccharide
B. Disaccharides
C. Polysaccharide
D. Heteropolymer.

Answer

### Step-by-Step Solution

1. **Identify the Nature of Ribose**:
- Ribose is a type of sugar that is naturally occurring. It is important to understand its classification within carbohydrates.

2. **Determine the Type of Sugar**:
- Ribose is classified as a pentose sugar, which means it contains five carbon atoms in its structure.

3. **Classify Ribose**:
- Since ribose is a simple sugar that cannot be hydrolyzed into smaller sugar units, it is classified as a monosaccharide.

4. **Understand Its Biological Role**:
- Ribose plays a crucial role in the structure of RNA (ribonucleic acid) and ATP (adenosine triphosphate), which are essential molecules in cellular processes.

5. **Eliminate Other Options**:
- Disaccharides are formed by the linkage of two monosaccharides (e.g., sucrose), and polysaccharides are long chains of monosaccharides (e.g., starch, glycogen). Heteropolymers consist of different types of monomers (e.g., proteins). Since ribose does not fit these definitions, these options can be eliminated.

6. **Conclusion**:
- Based on the classification and biological significance, the correct answer is that ribose is a monosaccharide.

### Final Answer
Ribose is a monosaccharide.

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