The purposes of cavity preparation is/are:: (A) Removal of all the defects of enamel, dentin  and cementum, (B) To  locate the  margins  of restoration as  conservatively  as  possible, (C) To allow for  esthetic and functional placement of restorative  material, (D) All of the above
Answer is D. Cavity design should be in biologic and structural harmony with tooth tissues.