Which of the following anesthetic agents is/are metabolized by plasma cholinesterase?
1. Prilocaine (Citanest).
2. Lidocaine (Xylocaine).
3. Mepivicaine (Carbocaine).
4. Procaine (Novocain).

(4) only

(1) (2) (3)

(1) and (3)

(2) and (4)

All of the above.