The correct answer is sympathetic nervous system.
In the given case, the harry is experiencing stress, which provokes the flight and fight syndrome. The sympathetic nervous system causes the release of adrenaline and noradrenaline causing change in physiological responses. During the flight and fight response, a hyperarousal occurs, which leads to the change in physiological responses. It causes the increased heart beat, increased blood pressure, anxiety, increase in pulse, increased sweating etc.
