Which of the following is/are desirable in an overdenture abutment?
1. Absence of extensive restorations.
2. Pre-existing endodontic treatment.
3. A 1:1 crown to root ratio.
4. A large band of attached gingiva.

(2) and (4)

(1) (2) (3)

(1) and (3)

(4) only

All of the above.