Final answer:
Statement 4 is correct; the fight-or-flight response was coined by Walter Cannon. This survival mechanism is still present in humans and prepares the body to face or escape danger, not save energy.
Step-by-step explanation:
Of the statements provided about the fight-or-flight response, number 4 is correct; the term was indeed coined by Walter Cannon. This physiological reaction is a survival mechanism that prepares the body to either confront or escape from immediate danger. It involves several changes including the increase of heart rate, the release of stress hormones, and the temporary suspension of non-essential bodily functions. Specifically, options 1 and 2 are incorrect as prolonged exposure to stress can actually undermine health, and the fight-or-flight response does not save energy but rather expends it to prepare the body for a quick reaction. Option 3 mischaracterizes the response which is actually adaptive, although in modern times constant activation due to psychological stress can lead to adverse health effects. And option 5 is incorrect because humans still retain the fight-or-flight response, although the type of stressors we face has evolved from physical to more psychological in nature.