A pontic replacing a mandibular first molar should be designed so that it(s)
1. gingival surface is concave and adapts closely to the ridge.
2. has open gingival embrasures.
3. conceals the porcelain to metal junction on its gingival surface.
4. gingival surface is convex in all directions.

(2) and (4)

(1) (2) (3)

(1) and (3)

All of the above.

(4) only