Violation
For an acid-etched Class III composite resin, the cavosurface margin of the cavity can be bevelled to 1. eliminate the need for internal retention. 2. improve convenience form. 3. aid in finishing. 4. increase the surface area for etching
(4) only
All of the above.
(2) and (4)
(1) and (3)
(1) (2) (3)