Without looking at the labels, Adrien placed four CDs in four cases. What is the probability that exactly two of the CDs are in the wrong cases? Express your answer as a common fraction.
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Without looking at the labels, Adrien placed four CDs in four cases. What is the probability that exactly two of the CDs are in the wrong cases? Express your answer as a common fraction.
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
\dfrac{1}{4}
Without looking at the labels, Adrien placed four CDs in four cases. What is the probability that exactly two of the CDs are in the wrong cases? Express your answer as a common fraction.
train