Definition: You need to answer a given question containing a blank (_). Your answer must be one of the two objects mentioned in the question, for example "trophy" and "suitcase". Your answer must not contain a word that is not present in the question. Please don't use articles (e.g., the, a) before the answer.
Input: Michael can't eat cheese, but he eats a whole lot of yogurt for breakfast. The _ bothers his stomach.

cheese