Question: Cardiologists in Toronto have developed two models that account for the benefits of exercise in people living with heart failure. Model A (Exercise -> Heart Failure) and Model B (Exercise -> Body Weight -> Pulmonary Function -> Heart Failure) differ in the nature and number of variables involved in the mechanisms leading to heart failure. What is the best argument based on the canons of science for selecting between Model A and Model B? Question options: Model A is better according to the principle of determinism Model A is better according to the principle of parsimony Model A is better according to the principle of testability Model A is better according to the principle of empiricism