Answer: Reappraisal
Explanation:
Reappraisal method is for reducing stress and tension in stressful situation when it cannot be avoided. Functioning in reappraisal is carried through decreasing or changing the influence of emotion through regulation or handling situation in form of positive way such as opportunity etc.
According to the question,Gwen is using reappraisal mechanism in which instead of getting tensed from test ,she is regulating her stress in the form of chance to show her studied learning and knowledge in test .