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

Example Input: Passage: Most fungi get organic compounds from dead organisms. Fungi use their hyphae to penetrate deep into decaying organic matter. They produce enzymes at the tips of their hyphae. The enzymes digest the organic matter so the fungal cells can absorb it. Fungi are the main decomposers in forests. They are the only decomposers that can break down cellulose and wood. They have special enzymes for this purpose. Answer: hyphae
Example Output: What do fungi use to penetrate deep into decaying matter?

Example Input: Passage: the fact that stars are made up of very lightweight hydrogen gas. Answer: hydrogen
Example Output: What type of gas are stars made up of?

Example Input: Passage: Humid continental climates are found between 40 and 60 north latitude. The northeastern U. S. has this type of climate. Summers are warm to hot, and winters are cold. Precipitation is moderate, and it falls year round. Deciduous trees grow in this climate ( Figure below ). They lose their leaves in the fall and grow new ones in the spring. Answer: deciduous
Example Output:
What do you call trees that lose their leaves in the fall and grow new ones in the spring?