Starch can be used as an indicator for the detection of traces of

Options

A. Glucose in aqueous solution
B. Protein in blood
C. Iodine in aqueous solution
D. Urea in blood

Answer

### Step-by-Step Solution:

1. **Understanding Starch as an Indicator**:
- Starch is a polysaccharide that is commonly used in laboratory settings as an indicator for certain chemical reactions.

2. **Identifying the Reaction**:
- Starch reacts specifically with iodine. When starch is mixed with iodine, it forms a complex that results in a color change.

3. **Color Change Observation**:
- The starch solution is initially colorless. Upon the addition of iodine, the solution changes color to blue or black. This color change indicates the presence of iodine.

4. **Conclusion**:
- Therefore, starch can be used as an indicator for the detection of traces of iodine in a solution.