There are two kinds of people living on an island, one is the person who tell the truth, the other is the person who tell the lie. One day, a person travels to the island and meets three island residents, A, B, and C. Then asked them who was the truth-teller and who was the lie-teller. A said: B and C are both lie-tellers. B said: I am a truth-teller. C Say: B is the one who tells lies.
How many of these three tell lies?
1