Amelie Is a First-Year University Student Who Is Living Away

Amelie is a first-year university student who is living away from home for the first time. She is living in a shared room on campus with her roommate, Anita. Though Amelie is very excited to be attending university, and so far she has managed to do well on her exams (usually earning a B+ or A-) , she still gets very anxious at certain times. Anita, on the other hand, is a little more laid back, does not care as much about her grades, and though she does fine on her exams (usually earning a B or B-) , she knows she could do better if she put her mind to it. Even though they did not know each other before becoming roommates, Amelie and Anita have become friends since the beginning of the school year.
-Amelie studies hard for her exams,but still worries she will fail.When is this stress beneficial

A) Stress is never beneficial.
B) When the level of stress is low enough to not impact her performance.
C) When the level of stress is high enough to maximize her performance.
D) When the level of stress is as high as possible.