What Conclusions Have Been Made Regarding Whether Male Erectile Disorder

What conclusions have been made regarding whether male erectile disorder has organic or psychological causes?

A) Recent research has shown that around 95% of all cases of erectile disorder have physical causes.
B) Most men suffering from erectile disorder can be classified into suffering either physical or psychological problems.
C) When erectile disorder has psychogenic causes,nocturnal penile tumescence (NPT) will not be lowered.
D) Psychological treatment can be very effective even when physical impairment is evident.
E) Erectile dysfunction may be caused be cardiovascular disease.