•crisis occurs when an individual: • a. is exposed to a precipitating stressor. • b. perceives a stressor to be threatening. • c. has no support systems. • d. experiences a stressor and perceives coping strategies to be ineffective.

I believe the answer is: D. experiences a stressor and perceives coping strategies to be ineffective.

When previous coping strategies couldn't handle ths stressor, people would experience a rise in anxiety that would often lead to many irrational/hastened behavior. As soon as crisis is handled succsfully , the likelihood of it repeating again in the future is dramatically decreased 

So you know what happened and so it doesn’t repeat it’s self