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

Example Input: Yeast fermentation causes holes in bread.
Example Output: What causes holes in bread?

Example Input: Control rods play an important role in the modulation of the nuclear chain reaction.
Example Output: What play an important role in the modulation of the nuclear chain reaction?

Example Input: Intercellular connections allow heterocysts to transport fixed nitrogen to neighboring cells and to receive carbohydrates.
Example Output:
What connections allow heterocysts to transport fixed nitrogen to neighboring cells and to receive carbohydrates?