Hi, What would the control group be for a group of experiments that are trying to figure out what kind of nutrients a mystery sample of food has in order to identify who left the food. The groups I have are:

Test one, each beaker is filled half way, beaker one with Liquid Gelatin, beaker two with water, and beaker three as your food sample.
One Vial of Biuret Solution is added to get a color reaction.

Test two, filled half way, one tube with vegetable oil, one with water, and one with your food sample. One vial of Sudan Red Solution is added for color reaction.

Test three, filled half way, polysaccharide solution in one tube, water in another, and the food sample. One vial of Lugol’s Solution for color reaction

Test four, tubes filled with Monosaccharide solution, water and food sample. One vial of Benedict’s Solution for color reaction

In Each test, the solution will be added to each of the small beakers to form a color reaction. The food sample will match the color of either positive or negative solutions.

Thank you! would award brainliest but I... don't know how to but I offer a lot of points.