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.

Example Input: Bill got a new king sized mattress but had to throw out his old queen bed frame because the _ was larger.
Example Output: mattress

Example Input: they had a pet tarantula that liked to climb the walls instead of the floor, because the _ were higher.
Example Output: walls

Example Input: He had a bowl of cereal with milk but it made him sick because the _ was expired.
Example Output:
milk