Which of the following is/are common to both gingival and periodontal pockets?
1. Apical migration of junctional epithelium.
2. Fibrotic enlargement of marginal tissue.
3. Bleeding upon probing.
4. Increased depth upon probing.

(4) only

(1) (2) (3)

(1) and (3)

(2) and (4)

All of the above.