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

[EX Q]: Monatomic ions form when a single atom gains or loses electrons.
[EX A]: What form when a single atom gains or loses electrons?

[EX Q]: Thermoregulation is the process when animals maintain an internal temperature.
[EX A]: What is the process when animals maintain an internal temperature?

[EX Q]: Hydrogen sulfide is a noxious and toxic gas produced from decaying organic matter that contains sulfur.
[EX A]:
Hydrogen sulfide is a noxious and toxic gas produced from decaying organic matter that contains what?