Not 100% sure but I'd go with A(:
B:
The fight or flight response is an automatic physiological reaction to an event that is perceived as stressful or frightening. The perception of threat activates the sympathetic nervous system and triggers an acute stress response that prepares the body to fight or flee. These responses are evolutionary adaptations to increase chances of survival in threatening situations. Overly frequent, intense, or inappropriate activation of the fight or flight response is implicated in a range of clinical conditions including most anxiety disorders. A helpful part of treatment for anxiety is an improved understanding of the purpose and function of the fight or flight response. This client information sheet describes the bodily consequences of the fight or flight response.
