Read the following paragraph and answer the question. Give ONLY the answer, no other words or explanation.

For example:

Answer: <most likely answer, as short as possible>.

Paragraph: 
If water is so simple, why is it special? Water is one of the few substances that exists on Earth in all three states of matter. Water occurs as a gas, a liquid and a solid. You drink liquid water and use it to shower. You breathe gaseous water vapor in the air. You may go ice skating on a pond covered with solid water — ice — in the winter.


Question: In how many states does water exist on earth?
three matter states
Three.