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

Example Input: Neutrophils provide an early, rapid, and nonspecific defense against invading pathogens.
Example Output: What provides an early, rapid, and nonspecific defense against invading pathogens?

Example Input: Rainfall weather phenomenon increases the rate of weathering in rock and soil.
Example Output: What weather phenomenon increases the rate of weathering in rock and soil?

Example Input: A waterfall a stream flows from a hard to  soft rock area, what is often formed.
Example Output:
When a stream flows from a hard to  soft rock area, what is often formed?