Answer:
The independent variable in this scenario would be the type of diet the dogs are given.
Step-by-step explanation:
The independent variable is the factor that the researchers manipulate or control in an experiment. In this case, the independent variable is the type of diet given to the dogs. Some dogs are given the new dog food designed to help them lose weight, while others continue with their normal diets. The researchers are testing whether the new dog food has an effect on the dogs' weight loss.