c. an event or situation that is beyond a person's ability to cope
Stressors refer to real or perceived factors that an individual finds overwhelming and outside his or her capacity to cope with. It is important to note that stressors are subjective and vary from person to person. For instance, while Cindy may perceive an essay-based exam as a stressor (something that is overwhelming beyond her ability to cope), Anna might not find essay-based exams as stressful.
