Given a scientific passage and an answer, generate a question for the given answer.

Example Input: Passage: Sperm are produced in the testes in the process of spermatogenesis. Answer: spermatogensis
Example Output: What process creates sperm?

Example Input: Passage: Simple carbohydrates can be classified in terms of chain length. Answer: simple
Example Output: Which carbohydrates can be classified in terms of chain length?

Example Input: Passage: Scientists compare the anatomy, embryos, and DNA of living things to understand how they evolved. Evidence for evolution is provided by homologous structures. These are structures shared by related organisms that were inherited from a common ancestor. Other evidence is provided by analogous structures. These are structures that unrelated organisms share because they evolved to do the same job. Answer: analogous structures
Example Output:
What type of structures evolved to do the same job by unrelated organisms?