## 91.

This time A and B made the following statements:

A: At least one of us is a liar.

B: $C-$ is a knight.

It is known that exactly one of them is a werewolf and that he is a knight. Who is the werewolf?
91. A must be a knight for the same reasons that V was a knight in the previous problem, namely: if A were a liar, then the statement that at least one of the three is a liar would be true, and we would arrive at a contradiction (the statement of a liar would be true). Since A is a knight, his statement is true, so at least one of the three is indeed a liar.

If V were a knight, then (due to V's statement) C would also be a knight, and all three would be knights. But in A's true statement, it is claimed that at least one of the three is a liar. Therefore, V must be a liar. Since V claims that C is a knight, C is actually a liar. Thus, A is the only knight. Therefore, A is a werewolf.