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

Input: Consider Input: Saturated hydrocarbons hydrocarbons contain only single bonds between carbon atoms.

Output: What hydrocarbons contain only single bonds between carbon atoms?


Input: Consider Input: Hookworms infest the intestines.

Output: What part of the body do hookworms infest?


Input: Consider Input: Leaves changing color on trees of these is the best sign that the fall season has begun.
Output: Which of these is the BEST sign that the fall season has begun?