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: Cynodonts became more mammal-like as they continued to evolve.
[A]: Cynodonts.


[Q]: Fact: a barometer is used to measure air pressure.
[A]: air pressure headache.


[Q]: Fact: Viruses contain DNA but not much else.
[A]:
DNA.