It summarizes a position that the argument is meant to discredit. It is the main conclusion of the argument. It undermines the argument's main conclusion. It is an assumption on which the argument depends.
Pain perception depends only partly on physiology. During World War II a significantly lower percentage of injured soldiers requested morphine than did civilians recuperating from surgery. The soldier' s response to injury was relief, joy at being alive, even euphoria; to the civilians, surgery was a depressing, calamitous event. So it would seem that the meaning one attaches to a wound can affect the amount of pain one perceives.
The claim that pain perception depends only partly on physiology figures in the argument in which one of the following ways?