Detailed Instructions: Given a scientific passage and an answer, generate a question for the given answer.
Q: Passage: The kidneys also secrete hormones that help maintain homeostasis. For example, they produce a hormone that stimulates bone marrow to produce red blood cells when more are needed. They also secrete a hormone that regulates blood pressure and keeps it in a normal range. Answer: the kidneys
A:
What organs secrete hormones that help maintain homeostasis?