Final answer:
The third common response to a threatening situation besides fight or flight is to freeze.
Step-by-step explanation:
Physically, a person can respond to a threatening situation with a fight, flee, or the third option often described is to freeze. This response is an involuntary human body response and is mediated by the nervous and endocrine systems during a perceived threat. It's commonly known as the fight-or-flight response, but recent understanding also includes the “freeze” response, or sometimes referred to as “fight, flight, fright, or freeze”.
While useful for survival in the face of physical danger, this response can be maladaptive in modern, largely psychological, stressors. Persistent and repeated exposure to stress can have negative health consequences, such as increased risk for heart disease and impaired immune function.
The sympathetic nervous system, which leads to physiological changes during the fight-or-flight response, is responsible for the body's reactions to emotional states, though originally it was simplified by Walter Cannon's catchy phrase that didn't capture the 'freeze' aspect.