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.

The camel left the alley and moved into the street, as the _ was safe for it at that time.
street

I wanted to learn to operate a bulldozer this summer at the mine, so I asked my uncle to show me how to operate the _ .
bulldozer

The bottle arranged on the shelf are about falling off because the _ is too small.

shelf