Research on Social Factors and the Risk of Posttraumatic Stress

Research on social factors and the risk of posttraumatic stress disorder suggests a role of social support in the etiology of posttraumatic stress disorder (PTSD) . It was found that

A) veterans who didn't face the embarrassment of being treated as heroes had lower rates of PTSD.
B) veterans from units that encouraged independence had lower rates of PTSD.
C) veterans who did not receive social support on their return had high rates of PTSD.
D) veterans who had high social support through the Veterans Administration still had high rates of PTSD.