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.

Q: 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 soil had less unfavorable physico-chemical properties?

A: Mike's.
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Q: Background Paragraph: Human populations are on the rise. The human population passed the 7 billion mark in October of 2011, and will pass 8 and 9 billion probably before the middle of the century. All these people will need resources such as places to live, food to eat, and water to drink, and they will use energy and create waste. Essentially, human population growth can effect all other causes of extinction. For example, more people on the Earth means more people contributing to global warming and pollution. More people also means more clearing of land for agriculture and development. Recall that development by humans often causes habitats to be destroyed. This destruction can force species to go extinct, or move somewhere else. 
Story: There are two identical neighboring planets, Krypton and Gotham, inhabited by the same species of creature. Both civilizations utilize the same technology and have the same city structures. However, the creatures on Krypton use substantially more energy than the people on Gotham. Furthermore, the inhabitants of Krypton have started clearing more land than Gotham. 
Question: Which planet has a larger population?

A: Krypton.
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Q: Background Paragraph: During late adulthood, the risk of developing diseases such as cardiovascular diseases and cancer continues to rise. Most people also have a decline in strength and stamina. Their senses may start failing, and their reflex time typically increases. Their immune system also doesn’t work as well as it used to. As a result, common diseases like the flu may become more serious and even lead to death. The majority of late adults develop arthritis, and as many as one in four develop Alzheimer’s disease. 
Story: Dr. Jones studied 2 groups of people to see the effects of aging on humans. Group A had people under 35 years old in it, while group B had people over 65. 
Question: Which group had a normal reflex time?

A:
Group A.
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