Test by which starch and cellulose can be distinguished from each other is `:

Options

A. reducing sugar test
B. analysis of products of hydrolysis
C. iodine test
D. Molisch test

Explanation

To distinguish between starch and cellulose, we can perform the iodine test. Here’s a step-by-step solution:

### Step-by-Step Solution:

1. **Understanding the Composition**:
- Both starch and cellulose are polysaccharides made up of glucose units. However, they differ in the type of glycosidic bonds that link these glucose molecules.

2. **Identifying Glycosidic Linkages**:
- Starch consists of two components: amylose (which has α(1→4) glycosidic bonds) and amylopectin (which has both α(1→4) and α(1→6) bonds).
- Cellulose, on the other hand, has β(1→4) glycosidic bonds between glucose units.

3. **Performing the Iodine Test**:
- In the iodine test, a solution of iodine (usually potassium iodide) is added to the sample.
- Starch reacts with iodine to form a blue-black complex due to the coiling of the amylose chain, which traps the iodine molecules.
- Cellulose does not form this complex and thus does not change color.

4. **Interpreting the Results**:
- If the solution turns blue-black, the sample contains starch.
- If there is no color change, the sample is likely cellulose.

5. **Conclusion**:
- The iodine test is effective in distinguishing between starch (which gives a blue-black color) and cellulose (which does not change color).

### Final Answer:
The test by which starch and cellulose can be distinguished from each other is the **iodine test**.

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