You are given a background paragraph that describes one or more causal or qualitative relationships such as a relationship in economics or a scientific law and a story that makes use of the concepts or the relationship described in the provided paragraph. You are also given a question about the story that requires an understanding of the relationship described in the background paragraph and the story. You need to come up with an answer to the given question; the answer will be a span from either the question or the story. In order to correctly answer the given question, you need to understand the relationship mentioned in the background paragraph and should be able to use it to understand that in the story. Your answer can not consist of any word that is not mentioned in any of these: the background paragraph, the story, or the question. You can directly copy and paste a span from the story or the question while answering the given question.

Input: Consider Input: Background Paragraph: In the U.S., the majority of electricity is produced by burning coal or other fossil fuels. This causes air pollution that harms the health of living things. The air pollution also causes acid rain and contributes to global warming. In addition, fossil fuels are nonrenewable resources, so if we keep using them, they will eventually run out. The main advantage of nuclear energy is that it doesn't release air pollution or cause the other environmental problems associated with the burning of fossil fuels. On the other other hand, radioactive elements are nonrenewable like fossil fuels and could eventually be used up.
Story: The U.S. produces its energy using fossil fuels, while Germany uses nuclear power plants as their main energy source. The two countries impact the environment in different ways.
Question: Which country contributes more to global warming?

Output: The U.S.

Input: Consider Input: Background Paragraph: The dangers of global warming are being increasingly studied by a wide global consortium of scientists. These scientists are increasingly concerned about the potential long-term effects of global warming on our natural environment and on the planet. Of particular concern is how climate change and global warming caused by anthropogenic, or human-made releases of greenhouse gases, most notably carbon dioxide, can act interactively, and have adverse effects upon the planet, its natural environment and humans' existence. It is clear the planet is warming, and warming rapidly. This is due to the greenhouse effect, which is caused by greenhouse gases, which trap heat inside the Earth's atmosphere because of their more complex molecular structure which allows them to vibrate and in turn trap heat and release it back towards the Earth. This warming is also responsible for the extinction of natural habitats, which in turn leads to a reduction in wildlife population.The most recent report from the Intergovernmental Panel on Climate Change (the group of the leading climate scientists in the world) concluded that the earth will warm anywhere from 2.7 to almost 11 degrees Fahrenheit (1.5 to 6 degrees Celsius) between 1990 and 2100.
Story: Two identical planets, Norlon and Bothar, have been discovered in a neighboring galaxy of ours. These two planets have the same type of atmosphere as Earth and are extremely similar to Earth in terms of topography and even species of animals that live on them. The main difference is that Norlon is inhabited by a species very similar to humans that emit a lot of carbon dioxide into the atmosphere. Bothar, however, has no such species on its planet.
Question: Does Norlon have more or less natural habitats than Bothar?

Output: less.

Input: Consider Input: Background Paragraph: Storing large volumes of data When storing XML to either file or database, the volume of data a system produces can often exceed reasonable limits, with a number of detriments: the access times go up as more data is read, CPU load goes up as XML data takes more power to process, and storage costs go up. By storing XML data in Fast Infoset format, data volume may be reduced by as much as 80 percent.
Story: Earl had a busy day storing XML. At 3 PM, he stored 11000 Gigabytes to the database. At 4 PM, he stored 22000 Gigabytes to the database. At 5 PM, he stored 33000 Gigabytes to the database. At 6 PM, he got dinner. At 7 PM, he stored 44000 Gigabytes to the database. At 8 PM, he stored 55000 Gigabytes to the database. At 9 PM, he went to sleep to finish storing XML tomorrow morning.
Question: What time did the access times go up: 4 PM or 9 PM?
Output: 4 PM.