A student investigated the enzymatic hydrolysis of starch using the enzyme amylase. They prepared three different reaction mixtures, A, B, and C. After incubation, they performed biochemical tests on a sample from each mixture. The results are shown in the table below:
| Reaction mixture | Iodine test | Benedict's test | Biuret test |
|---|---|---|---|
| A | Blue-black | Blue | Purple |
| B | Orange-brown | Brick-red | Purple |
| C | Orange-brown | Blue | Pale blue |
Identify the reaction mixture in which the enzyme has completely hydrolysed the substrate.
