Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Example Input: The newest, outer layers of secondary xylem are called sapwood.
Example Output: What are the newest, outer layers of secondary xylem called?

Example Input: Oxygen gas is given off by plants.
Example Output: Which gas is given off by plants?

Example Input: Acceleration function of the car is affected by the pedal that controls the amount of gas the engine gets.
Example Output:
What function of the car is affected by the pedal that controls the amount of gas the engine gets?