Which of the following can be done to edit a document for conciseness?

A) Clarify awkward references
B) Clarify sentence structure
C) Replace camouflaged verbs
D) Delete unnecessary words and phrases
E) Impose parallelism

To edit a document for conciseness, one should focus on getting rid of any unnecessary words or phrases. This can help to make the writing more clear and to the point. While the other options may also be important for editing, D is the most directly related to achieving conciseness.