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

[Q]: Renewable energy sources emit fewer or no greenhouse gases.
[A]: What type energy sources emit fewer or no greenhouse gases?


[Q]: Hookworms infest the intestines.
[A]: What part of the body do hookworms infest?


[Q]: Voltage is not the same as energy, but means the energy per unit charge.
[A]:
What term is not the same as energy, but means the energy per unit charge?