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: Cholesterol has been implicated in heart disease for decades. Atherosclerosis is a disorder of the arteries in which cholesterol and other materials are deposited on the interior of the arterial wall. These deposits lead to the formation of plaques that can restrict or even block the flow of blood through these blood vessels (see Figure below ). A decrease in the flow of blood can lead to high blood pressure and a lowered oxygen supply to the heart muscle. A complete blockage of blood flow to parts of the heart (a heart attack) can cause significant damage due to oxygen deprivation, in some cases leading to death. 
Story: Fred was a good athlete in his youth, and so was Vic. Fred started eating junk food and other fatty foods in his 30's. His cholesterol is very high now. Vic became a vegan later,and he is in a very good physical shape. 
Question: Which friend had a decreased blood flow to the heart?
Example Output: Fred.

Example Input: Background Paragraph: Mechanical weathering increases the rate of chemical weathering. As rock breaks into smaller pieces, the surface area of the pieces increases. With more surfaces exposed, there are more places for chemical weathering to occur ( Figure below ). Let’s say you wanted to make some hot chocolate on a cold day. It would be hard to get a big chunk of chocolate to dissolve in your milk or hot water. Maybe you could make hot chocolate from some smaller pieces like chocolate chips, but it is much easier to add a powder to your milk. This is because the smaller the pieces are, the more surface area they have. Smaller pieces dissolve more easily. 
Story: Rocks commonly found in Beijing are often found spread out in smaller pieces, whereas rocks in Montreal typically remain large in size and don't break apart as much. Both Beijing and Montreal are expected to experience bouts of acid rain in the upcoming weeks. 
Question: Which area's rocks will have higher rates of chemical weathering caused by the acid rain?
Example Output: Beijing.

Example Input: Background Paragraph: The primary role of red blood cells in the circulatory system is to transport oxygen to the tissues. The actual carrier of oxygen molecules is the protein hemoglobin, which binds to the oxygen and moves it throughout the body, releasing it in areas where the concentration of dissolved oxygen is low. A certain mutation in the gene for hemoglobin causes a slight change in the structure of this crucial protein, resulting in a disease called sickle-cell anemia. For people with this mutation, the hemoglobin produced by their red blood cells has a tendency to clump together, distorting the shape of the red blood cells and giving rise to the crescent-shaped cells seen above. By understanding the changes in structure that are the underlying cause of this disease, we have developed various ways to treat and manage this illness. 
Story: Doctors studied Dan, a normal patient, whit a normal number of red blood cells, and Jim, a patient that had sickle-cell anemia. The differences were remarkable in terms of overall well-being and health. 
Question: Which patient had fewer red blood cells, Dan or Jim?
Example Output:
Jim.