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

Carbon dioxide is an example of a material that easily undergoes sublimation.
Carbon dioxide is an example of a material that easily undergoes what?

Producing sperm and secreting testosterone are the main functions of male reproductive system system.
Producing sperm and secreting testosterone are the main functions of what system?

In invertebrates kind of animals does parthenogenesis occur.
In which kind of animals does parthenogenesis occur?