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.

Example Input: Fact: Viruses are not affected by antibiotics.
Example Output: Viruses smallpox.

Example Input: Fact: Producers are organisms that produce food for themselves and other organisms.
Example Output: Producers plants.

Example Input: Fact: Bottleneck effect occurs when a population suddenly gets much smaller.
Example Output:
Bottleneck effect.