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 lecture failed to present a good argument, but the essay did, as the _ was unclear in its meaning.

A: lecture
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Q: Andrew took notes and asked his teacher lots of questions in class, and he thought that the _ helped him prepare for the test.

A: notes
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Q: The stain in the bucket could not be cleaned with the brush because the _ is tough.

A:
stain
****