Question

Joseph lost his notebook. The teacher started questioning students about the theft.

Catherine said, "Tom did it", Tom said, "Alex did it" while, Martha said, "I did not do it" and Alex said, "Tom is lying about me".
If only one of the following statements is false, then which of the given options is correct?
•Catherine is a liar and Alex is telling the truth
•Martha stole the notebook and is lying
•Tom is a liar and Martha is telling the truth
•Alex stole the notebook

Answer 1

If Catherine is lying: Tom did not do it, but then Tom's statement that "Alex did it" would be true. This leads to a contradiction.

If Tom is lying: Alex did not do it, but then Alex's statement that "Tom is lying about me" would be false. This also leads to a contradiction.

If Martha is lying: She did it, but her statement contradicts itself.

If Alex is lying: Tom is telling the truth, which means Alex did it.

So, the correct option is: Alex stole the notebook.