The Principal Advantages of Using a Subject's Diary Either Instead

The principal advantages of using a subject's diary either instead of interview data, or to supplement interview data, would be which of the following?

A) Subjective perception at the time of the event is retrievable.
B) Private and clandestine topics that have previously been inaccessible may be obtained through diaries.
C) Diaries contain more truthful information than do other sources.
D) No contact with the subject is necessary.
E) Diaries may be used without consent.
F) Information obtained from a diary is thought to be more accurate than that obtained from pure recall.