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: A dilution effect is seen when animals living in a group "dilute" their risk of attack, each individual being just one of many in the group. George C. Williams and W.D. Hamilton proposed that group living evolved because it provides benefits to the individual rather than to the group as a whole, which becomes more conspicuous as it becomes larger. One common example is the shoaling of fish. Experiments provide direct evidence for the decrease in individual attack rate seen with group living, for example in Camargue horses in Southern France. The horse-fly often attacks these horses, sucking blood and carrying diseases. When the flies are most numerous, the horses gather in large groups, and individuals are indeed attacked less frequently. Water striders are insects that live on the surface of fresh water, and are attacked from beneath by predatory fish. Experiments varying the group size of the water striders showed that the attack rate per individual water strider decreases as group size increases. 
Story: Mike was visiting the African Savannah. One animal that interested him most was the African Buffalo. He noticed that the buffaloes would usually live in a large herd, often exceeding few hundreds. He noted that as case A. But sometimes the buffaloes would live in a small herd. He noted that as case B. Interestingly, there are incidents when an aggressive male buffalo would live by itself. He noted that as case C. 
Question: In which case the group would get more benefit as a whole, case A or case B?
Example Output: case B.

Example Input: Background Paragraph: So much rain falling so fast causes some of the damage from a hurricane. But a lot of the damage is caused by storm surge. Storm surge is very high water located in the low pressure eye of the hurricane. The very low pressure of the eye allows the water level to rise above normal sea level. Storm surge can cause flooding when it reaches land ( Figure below ). High winds do a great deal of damage in hurricanes. High winds can also create very big waves. If the large waves are atop a storm surge, the high water can flood the shore. If the storm happens to occur at high tide, the water will rise even higher. 
Story: Beach town was hit hard by the hurricane. Hill town was spared, being situated 50 miles south. the eye of the hurricane passed almost through Beach town. 
Question: Which town had less damage caused by storm surge?
Example Output: Hill.

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: Two students learned about respiratory systems in animals. Dana learned more about mammalian lungs, while Barry learned more about the lungs of birds. 
Question: Which student learned more about a network of very small blood vessels?
Example Output:
Dana.