instruction:
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.
question:
Preston liked learning violin better than piano at music class, because the _ hurt his back.
answer:
piano


question:
To activate the computer we required a new charger, as the _ was dependent on it.
answer:
computer


question:
The riot was scary because the street was filled with broken glass. The _ was sharp.
answer:

glass