Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Input: Consider Input: Producing sperm and secreting testosterone are the main functions of male reproductive system system.

Output: Producing sperm and secreting testosterone are the main functions of what system?


Input: Consider Input: Like skeletal muscle, cardiac muscle is striated.

Output: Like skeletal muscle, cardiac muscle is what?


Input: Consider Input: The mammalian middle ear has three bones.


Output: How many bones does the  mammalian middle ear have?