Answer the following question given this paragraph: 

All crocodilians have, like humans, teeth set in bony sockets. But unlike mammals, they replace their teeth throughout life. Crocodiles and gharials (large crocodilians with longer jaws) have salivary glands on their tongue, which are used to remove salt from their bodies. This helps with life in a saltwater environment. Crocodilians are often seen lying with their mouths open, a behavior called gaping . One of its functions is probably to cool them down.


Q: Lying with their mouths open, a behavior called gaping, probably serves what function for crocodiles?

 Choices:

- sleeping

- digesting

- eating

- cooling down

A:
cooling down
