On the fabled Island of Knights and Knaves, we meet three people, A, B, and C, one of whom is a knight, one a knave, and one a spy. The knight always tells the truth, the knave always lies, and the spy can either lie or tell the truth.
A says: "C is a knave."
B says: "A is a knight."
C says: "I am the spy."
Who is the knight, who the knave, and who the spy?