From studies and research, I believe the proper question would be:
"How do the animals satisfy their need for water?" or "How long do the animals live?"
Explanation 1:
When studying the desert, asking "Can you buy the animals in pet stores?" is not going to help you find information about the desert because it is not a question to get information about the desert, only information if you just buy it at your local pet shop.
Explanation 2:
Asking "How many offspring do the animals have?" does help us learn about animals, but we are trying to find information on the structure of the desert in which the animals live in. We are not looking for how many children the animals will have because it doesn't fully relate to the question we would be asking.
Side Note: Offsprings mean children.
Hope this helps!
~Hocus Pocus
