instruction:
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 need to come up with a question about the story that requires an understanding of the relationship described in the background paragraph. The generated question should not be answerable without both the background and story. Write a question about the story that requires a relationship in the background paragraph to answer. Check whether your question requires both the background paragraph and the story to answer. If your question can be answered by only one of these, try to rewrite your question so that it requires both. Note that "flipping" a word in the question can give rise to a new question where the answer will be different from the original question. Often, "flipping" a word gives rise to flipping the direction of the relationship, for example, from "increase" to "decrease."
question:
Background Paragraph: When soil is flooded, hypoxia develops, as soil microorganisms consume oxygen faster than diffusion occurs. The presence of hypoxic soils is one of the defining characteristics of wetlands. Many wetland plants possess aerenchyma, and in some, such as water-lilies, there is mass flow of atmospheric air through leaves and rhizomes. There are many other chemical consequences of hypoxia. For example, nitrification is inhibited as low oxygen occurs and toxic compounds are formed, as anaerobic bacteria use nitrate, manganese, and sulfate as alternative electron acceptors. The reduction-oxidation potential of the rhizhosphere decreases and metal ions such as iron and manganese precipitate. Aerenchyma is a modification of the parenchyma. 
Story: John is a soil scientist. He has been studying the lands near Mississippi delta. He noticed cases of hypoxia in that are. He labeled that study as case A. To compare that to other areas he visited Arizona. There he didn't see any occurrence of hypoxia. He labeled that case as case B.
answer:
In which case microorganisms would cause less oxygen in the soil, case A or case B?


question:
Background Paragraph: One result of air pollution is acid rain. Acid rain is precipitation with a low (acidic) pH. This rain can be very destructive to wildlife. When acid rain falls in forests, freshwater habitats, or soils, it can kill insects and aquatic life. It causes this damage because of its very low pH. Sulfur oxides and nitrogen oxides in the air both cause acid rain to form ( Figure below ). Sulfur oxides are chemicals that are released from coal-fired power plants. Nitrogen oxides are released from motor vehicle exhaust. 
Story: Beijing recently significantly increased the amount of cars on the roads there through mandatory price cuts for all motor vehicles.  In Montreal, the number of cars on the roads has decreased drastically recently through public transportation initiatives and public advertising campaigns encouraging biking and walking.
answer:
Which area will produce fewer nitrogen oxides?


question:
Background Paragraph: About 10% of sedimentary rocks are limestones. The solubility of limestone in water and weak acid solutions leads to karst landscapes, in which water erodes the limestone over thousands to millions of years. Most cave systems are through limestone bedrock. 
Story: The Berg mountains in Berg county are of a volcanic nature, very massive, few caves. The Gorge mountains in Gorge county are made of sedimentary rocks, predominantly limestone. They were exposed to water and that lead to karst lanscapes, caves, blue holes, stalactites and stalagmites.
answer:

Which of the two mountains eroded faster over time?