We still don't understand the influence of the mind's power over the body, nor do we understand why there should be such power. All we can say for certain is that the mind does have power over the body in very many different ways.  If a man is told that he is at the North Pole and he believes what he is told, he'll show physical signs which suggest that his body is reacting as though he were at the North Pole. He'll go pale and shiver. When the film Lawrence of Arabia was shown, cinema managers around the world reported that the sales of ice cream rocketed. The endless desert scenes had made the moviegoers feel uncomfortably hot.  Hypnotists use the power of the mind over the body in order to use their influence. The hypnotist must only convince the patient that something is true, and the patient will act accordingly. If he convinces the patient that his arms are as heavy as lead, then the patient will be unable to lift his arms. If he convinces the patient that a piece of ice is a hot iron and he then touches the patient's skin with the ice, a blister will develop. The body will react to the suggestion and not to the reality, and signs of a real burn will appear. From the passage, we can imagine that people watching a film about the North Pole would probably want   _  .
an ice cream a cold shower a hot drink a hot iron