Task: Question Generation
Input (English): Background Paragraph: In the U.S., the majority of electricity is produced by burning coal or other fossil fuels. This causes air pollution, acid rain, and global warming. Fossil fuels are also limited and may eventually run out. Like fossil fuels, radioactive elements are limited. In fact, they are relatively rare, so they could run out sooner rather than later. On the other hand, nuclear fission does not release air pollution or cause the other environmental problems associated with burning fossil fuels. This is the major advantage of using nuclear fission as a source of energy. 
Story: An alien passing by Earth in a UFO to write a report on two random cities so that his government can better understand what the people of Earth are like. He first flies over Nillmar, a city in France, which uses burns coal as its main production of electricity. After observing Nillmar, the alien flies over to Springfield, a city in the United States, that decided to use nuclear power to fuel itself. After taking his notes, the alien leaves and is eager to report back to his superiors about what he discovered.
Output (English): What city is contributing more to global warming?