TASK 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.
PROBLEM: The thief put all of the items from the safe into his bag until the _ was full.

SOLUTION: bag

PROBLEM: Under the reflection of the light bulb, i can only see the clock frame and not the face because the _ is unreflective.

SOLUTION: frame

PROBLEM: The car engine outperformed the bus engine simply because the _ was inefficient during the test run.

SOLUTION:
bus