Which of the Following Is/are Diagnostic Criteria for Primary Insomnia

Which of the following is/are diagnostic criteria for primary insomnia?

A) The sleep disturbance is defined as difficulty initiating or maintaining sleep,or non-restorative sleep,for at least 1 month
B) The disturbance does not occur during the course of another mental disorder
C) The sleep disturbance or associated daytime fatigue causes clinically significant distress or impairment in social,occupational,or other important areas of functioning
D) All of the above