You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
In this task, you are given a question and a corresponding answer. Your task is to generate a fact statement that is useful in answering the given question.

Question: Frilled sharks and angler fish live far beneath the surface of the ocean, which is why they are known as? Answer: deep sea fish
Solution: deep sea animals live deep in the ocean.
Why? This sentence is useful when answering the given question. The sentence provides the information that animals who live deep in the ocean are called deep sea fish. This is a good output. 

New input: Question: A way in which humans may cause pollution to the environment is? Answer: using bug killer on crops.
Solution:
pollution is when humans pollute the environment with pollutants