Question 19
Lý Thông, Thạch Sanh, and a Knight bring the head of Xà Tinh to the king. The king asks, "Who killed Xà Tinh?"
Lý Thông says, "I killed Xà Tinh."
Thạch Sanh says, "The Knight killed Xà Tinh."
The Knight says, "Lý Thông did not kill Xà Tinh."
Exactly one of the three is lying. Who killed Xà Tinh?
Lý Thông says, "I killed Xà Tinh."
Thạch Sanh says, "The Knight killed Xà Tinh."
The Knight says, "Lý Thông did not kill Xà Tinh."
Exactly one of the three is lying. Who killed Xà Tinh?