In a controlled experiment, if a researcher wants to examine the effect of a high-calorie diet on an animal's weight, which of the two would be the independent variable?

High calories diet

Explanation:

Independent variable can be defined as the factors which the experimenter can control and the the dependent variable depends on the independent variable.

Here, the experiment is to test the effect of high calorie diet on the animal's weight.

The experiment is to test whether the animals gain weight if supplied with high calorie diet.

So, the independent variable in the experiment is high calorie diet and dependent variable is weight of animal.