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.

[EX Q]: 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: Carl had a busy day storing XML. At 1 PM, he stored 1000 Gigabytes to the database. At 2 PM, he stored 2000 Gigabytes to the database. At 3 PM, he stored 3000 Gigabytes to the database. At 4 PM, he got dinner. At 5 PM, he stored 4000 Gigabytes to the database. At 6 PM, he stored 5000 Gigabytes to the database. At 7 PM, he went to sleep to finish storing XML tomorrow. 
Question: What time did storage costs go up:  3 PM or 7 PM?
[EX A]: 3 PM.

[EX Q]: Background Paragraph: Leucism (/ˈluːsɪzəm, -kɪz-/)[1][2][3] is a condition in which there is partial loss of pigmentation in an animal resulting in white, pale, or patchy coloration of the skin, hair, feathers, scales or cuticle, but not the eyes.[3] It is occasionally spelled leukism. Unlike albinism, it is caused by a reduction in multiple types of pigment, not just melanin. 
Story: There is a strange phenomenon going on in Siberia. Biologist noticed that 60 percent of the Siberian Tigers have leucism, and another 40 percent have albinism. They labeled the first group as group A and the latter one as group B. They need to find the reasons for this phenomenon. 
Question: Which group would have multiple types of reduced pigment?
[EX A]: group A.

[EX Q]: Background Paragraph: Weather conditions include air temperature, humidity, wind speed and direction, and precipitation. Weather is temporary. People in many states have the joke, "if you don't like the weather, wait five minutes and it will change." One way to change the weather is to have a different air mass move over the region. Interactions between air masses bring about a lot of weather. For example, thunderstorms and tornadoes form along a front. A front is where air masses meet. Fronts can bring about blizzards, thunderstorms, tornadoes and other types of weather. Weather prediction is much better than it was in past years. This is due in part to information from satellites. Climate is the long-term average of weather. The climate of a location depends on its latitude, position relative to the atmospheric circulation cells, position on a continent, altitude, and position relative to mountains. Areas with roughly the same climate make up a climate zone. The organisms that live within a climate zone create a unique biome. Earth's climate has changed throughout the planet's history. Earth was frigid at the end of the Pleistocene ice age, but has been warming since then. Since the Industrial Revolution the pace of warming has increased. In the past few decades the rate has really intensified. This is related to greenhouse gas emissions, primary from fossil fuel burning. The destruction of forests also increasing warming. The effects of global warming are already being seen. Treaties and voluntary actions are needed to reduce emissions to lessen the amount of global warming that will take place in the future. 
Story: Rob always confuses the terms climate and weather. He found it's better to compare them if he needs to learn more about their characteristics. To make things easier, he labeled the weather of his city as char A. Then he labeled the climate of this city as char B. Once finished with learning their characteristics, Rob focused on climate change issues. For that, he labeled the climate of present time as char C and climate just before industrial revolution as char D. 
Question: Which one would be warmer, char C or char D?
[EX A]:
char C.