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Puzzles/Logic puzzles/Knights, Knaves & Spies/Solution
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Puzzles | Logic puzzles | Knights, Knaves & Spies | Solution
A - Knight
B - Spy
C - Knave
Reasoning
B is not the knight, since if he is, then A would also be the knight.
C is not the knight, since his statement would then be a lie. Therefore A is the knight.
Hence C is the knave, and B is the spy.