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.

Fact: pollutants have a negative impact on the environment.
environment health.

Fact: medicine is used for curing people when they are sick.
Medicine prescription.

Fact: sunlight and rain can cause a rainbow.

a rainbow is a.