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 Input:
Background Paragraph: As time passes, the number of HIV copies keeps increasing, while the number of helper T cells keeps decreasing. The graph in Figure below shows how the number of T cells typically declines over a period of many years following the initial HIV infection. As the number of T cells decreases, so does the ability of the immune system to defend the body. As a result, an HIV-infected person develops frequent infections. Medicines can slow down the virus but not get rid of it, so there is no cure at present for HIV infections or AIDS. There also is no vaccine to immunize people against HIV infection, but scientists are working to develop one. 
Story: Jacob recently contracted the HIV virus and is going to his first support meeting. While there, he meets Dan and strikes up a conversation with him. Dan says that he has had HIV for over a decade at this point and has learned ways to live with it. He is able to give Jacob some good advice on how to handle things and Jacob is very grateful to have someone to talk with. 
Question: Which person's body will struggle less to defend from the HIV infection?

Ex Output:
Jacob.


Ex Input:
Background Paragraph: Air pollution is harmful to human beings and other living things. About 22 million people die from air pollution each year. Breathing polluted air increases the risk of developing lung diseases such as asthma and lung cancer. Breathing bad air also increases the chances of dying from other diseases. Children are most likely to be affected by air pollution. That’s because their lungs are still developing and growing. Children also take in more air for their size than adults do. Some air pollutants damage the environment as well as the health of living things. The type of damage depends on the pollutant. Air pollution can also harm the environment. 
Story: Two sister cities were part of an air pollution study. While Prague had big air pollution problems, Belfast was eco-friendly and its inhabitants were healthy. 
Question: Which city had fewer people with an increased chance of developing asthma?

Ex Output:
Belfast.


Ex Input:
Background Paragraph: Alkali, or Alkaline, soils are clay soils with high pH (> 8.5), a poor soil structure and a low infiltration capacity. Often they have a hard calcareous layer at 0.5 to 1 metre depth. Alkali soils owe their unfavorable physico-chemical properties mainly to the dominating presence of sodium carbonate, which causes the soil to swell[1] and difficult to clarify/settle. They derive their name from the alkali metal group of elements, to which sodium belongs, and which can induce basicity. Sometimes these soils are also referred to as alkaline sodic soils.
Alkaline soils are basic, but not all basic soils are alkaline. 
Story: Mike grew tomatoes on his parcel of land and so did John. Mike's attempt was very successful, because he adjusted the soil's pH to a viable level for growing vegetables, and John didn't. Both parcels had soils with lots of sodium carbonate in them. John's experiment failed. 
Question: Which parcel had a less alkaline soil?

Ex Output:

Mike's.