## 79.

On charges of robbery, A, B, and C were brought to court. The following has been established:

1) At least one of the three defendants is guilty.
2) If A is guilty and B is not guilty, then C is not guilty.

This information is insufficient to prove the guilt of each of the three defendants individually, but it does allow for the selection of two defendants, one of whom is definitely guilty. Which two defendants are being referred to?
79. Two defendants, one of whom must be guilty, are V and C. Indeed, suppose A is not guilty. Then, by statement (1), V or C must be guilty. On the other hand, suppose A is guilty. If V is guilty, then at least one of V and C is definitely guilty. But suppose V is not guilty. Then A is guilty, and V is not guilty. Therefore, by statement (2), C must be guilty, that is, in this case, either V or C is guilty.