Which of the following is used in a colour test of amino acid ?

Options

A. Ninhydrin
B. Cyanogen bromide
C. Trypsin
D. Chymotrypsin

Explanation

To determine which substance is used in a color test for amino acids, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the substance that is used in a color test for amino acids.

2. **Identify the Options**: Although the options are not provided in the question, we know that Ninhydrin is commonly used in such tests.

3. **Research Ninhydrin**: Ninhydrin, also known as 2,2-dihydroxyindane-1,3-dione, is a chemical reagent that reacts with amino acids.

4. **Reaction with Amino Acids**: When Ninhydrin is added to an amino acid solution, it undergoes a chemical reaction that produces a deep blue color. This reaction is specific to amino acids, which is why Ninhydrin is used in color tests.

5. **Conclusion**: Based on the information gathered, the correct answer to the question is Ninhydrin.

### Final Answer:
Ninhydrin is used in a color test for amino acids.

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