In this task, you are given a sentence and a question, you would be asked to create the answer which is contained in the sentence provided.
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Question: Sentence: Tributaries is the term for small streams. Question: What is the term for small streams?

Answer: tributaries


Question: Sentence: A wall of rocks or concrete a called a groin. Question: What is a wall of rocks or concrete called?

Answer: groin


Question: Sentence: People stopped adding lead to gasoline because of environmental pollution. Question: Why did people stop adding lead to gasoline?

Answer:
environmental pollution