To test the effectiveness of a diet cat food, scientists divided a group of overweight cats into a control and treatment group.
The cats in the control group ate their regular food. The cats in the treatment group received a measured portion of diet cat food twice a day. After two months, the cats in the treatment group had lost an average of 1.2 lb, and the cats in the control group had gained an average of 0.1 lb. State the Subjects: