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

Example Input: Passage: Cloud types include cirrus, stratus, and cumulus. Answer: clouds
Example Output: Cirrus, stratus, and cumulus are types of what?

Example Input: Passage: Bacteria called cyanobacteria are very important. They are bluish green in color (see Figure below ) because they contain chlorophyll. They make food through photosynthesis and release oxygen into the air. These bacteria were probably responsible for adding oxygen to the air on early Earth. This changed the planet's atmosphere. It also changed the direction of evolution. Ancient cyanobacteria also may have evolved into the chloroplasts of plant cells. Answer: chlorophyll
Example Output: Cyanobacteria are bluish green in color because they contain what?

Example Input: Passage: Volume is a measure of the amount of space that a substance or an object takes up. The basic SI unit for volume is the cubic meter (m 3 ), but smaller volumes may be measured in cm 3 , and liquids may be measured in liters (L) or milliliters (mL). How the volume of matter is measured depends on its state. Answer: volume
Example Output:
What is a measure of the amount of space that a substance or an object occupies?