Polysaccharides can be tested by

Options

A. Iodine
B. HCl
C. KCl
D. `KNO_(3)`

Answer

To determine how polysaccharides can be tested, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Polysaccharides**:
- Polysaccharides are complex carbohydrates made up of long chains of monosaccharide units. Common examples include starch, glycogen, and cellulose.

2. **Identifying the Test for Starch**:
- One of the most well-known polysaccharides is starch. To test for the presence of starch, a specific reagent is used.

3. **Using Iodine Solution**:
- The iodine test is a classic method for detecting starch. Iodine solution, which is typically brown or yellow, is added to the sample being tested.

4. **Observing Color Change**:
- If starch is present in the sample, the iodine will react with it, resulting in a color change to blue or black. This color change indicates a positive test for starch.

5. **Evaluating Other Options**:
- The other options provided (HCl, KCl, KNO3) do not specifically test for polysaccharides.
- HCl is a strong acid and does not indicate the presence of polysaccharides.
- KCl is a neutral salt and does not react with polysaccharides.
- KNO3 is a strong oxidizer and is not used for testing polysaccharides.

6. **Conclusion**:
- Based on the above steps, the correct answer to the question "Polysaccharides can be tested by" is option A: Iodine (IOD).