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]: The mother attended the baby's baptism while the father stayed home, since _ 's presence was optional for the ritual.
[A]: father


[Q]: As the gas filled the room, most people opted for the mask instead of the bag since the _ was efficient.
[A]: mask


[Q]: I bought a new pipe, but it didn't fit into the socket, because the _ was too thick.
[A]:
pipe