Sandy, Sam, and Steve are observing a cat in the distance. The cat is eating something but it\textquotesingle s hard to tell what it is.  Sandy says:"The cat is eating fish."  Sam says:"I agree with Sandy!"  Steve says: "The cat is eating meat."  Then they come closer and realize only one of them guessed right.  The cat is eating . 
选项为:A:　meat  B:　fish  C:　Not certain  请回答其中一个选项.