The obesity invariably associated with some high-fat diets is caused by an absence in these diets of certain nutrients that are necessary for an active metabolism, not by excessive caloric intake.
Your task
Break the argument into its conclusion and evidence, then do exactly what the question stem asks with that structure.
Common trap
Answers that sound relevant to the topic but don't connect to the argument's actual reasoning.
Winning move
Predict what a right answer must do, then test each choice against the conclusion-evidence gap.