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

Example Input: Passage: Waves are characterized by their ability to constructively and destructively interfere . Light waves which interfere with themselves after interaction with a small aperture or target are said to diffract . Answer: diffract
Example Output: Light waves which interfere with themselves after interaction with a small aperture or target are said to what?

Example Input: Passage: Population density is the average number of individuals in a population per unit of area or volume. For example, a population of 100 insects that live in an area of 100 square meters has a density of 1 insect per square meter. If the same population lives in an area of only 1 square meter, what is its density? Which population is more crowded? How might crowding affect the health of a population?. Answer: population density
Example Output: What is the term for the average number of individuals in a population per unit of area or volume?

Example Input: Passage: Bone marrow is a soft connective tissue inside pores and cavities in spongy bone. Bone marrow makes blood cells. Answer: bone marrow
Example Output:
What is a soft connective tissue inside pores and cavities in spongy bone?