Answer: C) If the cat meows one more time – I know he will – I am going to have to get the treats.
Step-by-step explanation: One of the most common uses of dashes is to introduce (and conclude) an additional information in a sentence or paragraph. In the given sentence, the additional information is "I know he will" (notice that if we remove this information, the sentence still makes complete sense), so that phrase should be between dashes, therefore, the correct answer is the corresponding to option C.