The following one is smallest.

Options

A. maltose
B. Cellulose
C. Glycine
D. Cellbiose

Answer

To determine which of the given options is the smallest molecule, we need to analyze each option carefully.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are maltose, cellulose, cellobiose, and glycine.

2. **Analyze Maltose**:
- Maltose is a disaccharide composed of two glucose molecules linked by an alpha-1,4 glycosidic bond.
- The molecular formula for maltose is C12H22O11.

3. **Analyze Cellulose**:
- Cellulose is a polysaccharide made up of many glucose units (approximately 6000) linked together in a linear chain.
- It is a much larger molecule compared to disaccharides.

4. **Analyze Cellobiose**:
- Cellobiose is also a disaccharide, similar to maltose, but it consists of two glucose molecules linked by a beta-1,4 glycosidic bond.
- Its molecular formula is also C12H22O11, making it similar in size to maltose.

5. **Analyze Glycine**:
- Glycine is the simplest amino acid and has the structure: NH2-CH2-COOH.
- Its molecular formula is C2H5NO2, which is significantly smaller than both maltose and cellobiose.

6. **Comparison**:
- Maltose and cellobiose are both disaccharides with the same molecular formula, while cellulose is a large polysaccharide.
- Glycine, being an amino acid, has a much smaller molecular structure compared to the other three options.

7. **Conclusion**:
- Among the options, glycine is the smallest molecule.

### Final Answer:
The smallest molecule among the given options is **glycine**.

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