The correct answer is fight or flight. The fight or flight response also called acute stress response, is a physiological response to a perceived attack, threat or in general any stressful event. This reaction consists the first stage of the general adaptation syndrome, which is the mechanism that regulates the response to stressful situations.
This response consists of an activation of the autonomic nervous system and a cascade of hormones, including catecholamines, cortisol, estrogen, testosterone, and dopamine. This hormonal cascade results in many physiological changes which prepare the body for action.