Various Psychological Factors Have Been Implicated in Chronic Fatigue Syndrome

Various psychological factors have been implicated in chronic fatigue syndrome (CFS) .For example, in examining the role of cognitive factors in the psychological adjustment to the illness of patients with CFS, researchers found that feelings of helplessness and depression were associated with another factor.What is this other factor?

A) perceiving the cause of CFS as external and believing that there is no cure for CFS
B) believing that CFS is just "in one's head" and believing that there is no cure for CFS
C) perceiving the cause of CFS as external and believing that one has no control over the disorder
D) perceiving the cause of CFS as internal and believing that one has no control over the illness