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:
She had a lower back pain but her headache was gone, so the _ problem was comforting her now.
answer:
headache


question:
Bob planted a row of trees rather than a row of shrubs because the _ offered more privacy.
answer:
trees


question:
The wheels on the bicycle were better than the tires on the car, because the _ were very used.
answer:

tires