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.

Q: Fact: nuclear reactions in stars causes stars to produce light.

A: light contains photons.
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Q: Fact: Bird eggs have hard, calcium carbonate shells.

A: Bird eggs have hard, calcium carbonate shells.
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Q: Fact: HIV infects and destroys helper T cells.

A:
HIV aids.
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