In this task, you need to write a topic word from the given fact. The topic word must have at least one word overlap with the given fact. The topic word often involves adding a new word from a related concept. In your topic word, use at least one word from the given fact. Topic words with two or more words work best.
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Question: Fact: Air pollution harms the respiratory and circulatory systems.

Answer: Air pollution caused by.


Question: Fact: Testosterone stimulates the reproductive organs to develop into male organs.

Answer: male organ penis.


Question: Fact: if gas is heated then that gas will expand.

Answer:
expand heat density gas.