Answer:
An identical setup but replacing the enzyme with an equal volume of water
Step-by-step explanation:
When carrying out any experiment, it is important to set out a control in order to increase the reliability of the data and results.
The control minimizes the effects of variables other than the independent variable.
In the above experiment, starch has to be eliminated and replaced with water. Water does not have starch hence the digestive enzyme being tested will not have any effects making the data and results from the experimental group reliable.