3. Xiaodong, Xiaoxi, Xiaonan, and Xiaobei, four children, were playing together when they found a red scarf and handed it to the teacher. The teacher asked who found it? Xiaodong said it wasn't Xiaoxi; Xiaoxi said it was Xiaonan; Xiaonan said Xiaodong was wrong; Xiaobei said Xiaonan was also wrong. Only one of them was right, and this person is ( ).
(A) Xiaodong
(B) Xiaoxi
(C) Xiaonan
(D) Xiaobei
【Answer】C
【Analysis】Dong: It's not Xi.
Xi: It's Nan.
Nan: Dong is wrong.
Bei: Nan is also wrong.

From the conversation, it can be seen that what Nan and Bei said are contradictory, so one of them must be correct. Therefore, Dong must be wrong. Since Dong is wrong, it means that Nan is right.
【Difficulty】
【Knowledge Point】Logical Reasoning