Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: Figure 43.17 Rising and falling hormone levels result in progression of the ovarian and menstrual cycles. (credit: modification of work by Mikael Häggström). Answer: hormones

Answer: Rising and falling levels of what will result in progression of the ovarian and menstrual cycles?


Question: Passage: Simple carbohydrates can be classified in terms of chain length. Answer: simple

Answer: Which carbohydrates can be classified in terms of chain length?


Question: Passage: Arthropods are the largest phylum in the animal kingdom. Answer: arthropods

Answer:
What are the largest phylum in the animal kingdom?


