Which term is defined as circumstances that threaten,or are perceived to threaten,one's well-being and tax one's coping abilities

A)  pressure
B)  conflict 
C)  stress
D)  frustration

Stress is defined as circumstances that threaten, or are perceived to threaten, one's well-being and tax one's coping abilities. Pressure refers to the demands placed on a person to perform or complete a task in a certain way and within a certain time frame. Conflict refers to a situation where a person faces a difficult choice between two or more options. Frustration refers to the feelings of disappointment and annoyance that arise when a person is unable to achieve a desired goal or outcome.