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.

[Q]: Jane was starring at the sea until the sun set behind it and now just the _ is invisible.
[A]: sun


[Q]: The car engine outperformed the bus engine simply because the _ was inefficient during the test run.
[A]: bus


[Q]: I tried to clean the pipe with the brush but I couldn't because the _ was too big.
[A]:
brush