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.
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Question: They wondered if the blue powder or the red powder would dissolve faster, but they couldn't open the _ one.

Answer: blue


Question: He could either build the birdhouse or the tree-house first, but the _ would take less time to construct.

Answer: birdhouse


Question: Liz was making a pizza with tomato sauce, cheese, pepperoni, and basil. The first thing she used was the _ .

Answer:
tomato sauce