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.

Example Input: Background Paragraph: The lungs of mammals are unique in having alveoli . These are tiny, sac-like structures. Each alveolus is surrounded by a network of very small blood vessels (see Figure below ). Because there are millions of alveoli in each lung, they greatly increase the surface area for gas exchange between the lungs and bloodstream. Human lungs, for example, contain about 300 million alveoli. They give the lungs a total surface area for gas exchange of up to 90 square meters (968 square feet). That’s about as much surface area as one side of a volleyball court!. 
Story: David is investigating the breathing process of different organisms. He found that humans have alveoli to help them with gas exchange. He got curious about other organisms that do not have alveoli. To compare these two groups he labeled organisms with alveoli as group A and organisms without alveoli as group B. 
Question: Would group A have greater or smaller gas exchange than group B?
Example Output: greater.

Example Input: Background Paragraph: Before iodized salt was developed, some people experienced a number of developmental difficulties, including problems with thyroid gland function and mental retardation. In the 1920s, we learned that these conditions could usually be treated easily with the addition of iodide anion to the diet. One easy way to increase iodide intake was to add the anion to table salt. This simple step greatly enhanced health and development. Large amounts of iodide ion are also found in seaweed such as kelp (see picture above) and saltwater fish. 
Story: People from two villages ate lots of salt. People from Salt village used regular salt, while people from Sand village people used iodized salt in their diets, after talking to specialists. 
Question: Which village had fewer people experience developmental difficulties?
Example Output: Sand.

Example Input: Background Paragraph: Turner et al (2006) derived crash prediction models for this report’s predecessor and found a
pronounced ‘safety in numbers’ effect in the models. Using the crash prediction model for mid-block
locations, generic motorist and cyclist volumes can be used to demonstrate the impacts on the
expected crash rate of varying motor vehicle and cycle volumes. As shown in figure 2.20, an increase
in the proportion of cyclists to the overall traffic volume causes an increase in expected crashes at
mid-block locations, but the crash rate increases at a decreasing rate. That is to say, the crash rate per
cyclist goes down as the cycle volume increases. 
Story: Berg village and Hill village are renowned for the high number of cyclists living there. Berg village dealt with many traffic casualties because of narrower streets and lanes, While Hill village had wide streets, more traffic signals and a greater number of cyclists. 
Question: Which village had a smaller traffic volume?
Example Output:
Berg.