A, who was in a severe need of money, waited in an alley until another person, B walked by on the street. Then, stepping out of the alley, he stuck his hand in his pocket with his finger thrust forward and said, "I've got a gun in this pocket." Snatching B's purse with his other hand, he ran away because B thought that he had a gun, he did not attempt to stop him. Select the offence of which A is most likely to be properly convicted. (16)
(a) Cheating
(b) Decoity
(c) Robbery
(d) Extortion