Detailed Instructions: Given a scientific passage and an answer, generate a question for the given answer.
Q: Passage: Sponges have an internal skeleton that gives them support and protection. An internal skeleton is called an endoskeleton . A sponge endoskeleton consists of short, sharp rods called spicules (see Figure below ). Spicules are made of silica, calcium carbonate, or spongin, a tough protein. They grow from specialized cells in the body of the sponge. Answer: endoskeleton
A:
Sponges possess an internal skeleton called what?