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: Depleted soils can be protected from soil erosion by groundcover plants such as naturally growing grasses in agroforestry systems. These help to stabilise the soil as they increase cover compared to short-cycle cropping systems. Soil cover is a crucial factor in preventing erosion. Cleaner water through reduced nutrient and soil surface runoff can be a further advantage of agroforestry. The runoff can be reduced by decreasing its velocity and increasing infiltration into the soil. Compared to row-cropped fields nutrient uptake can be higher and reduce nutrient loss into streams.Further advantages concerning plant growth:. 
Story: Two neighboring farms both had depleted soils due to intensive agricultural practices for decades. Apple far decided to start an agroforestry system and other methods to protect their depleted soils, while Pear farm did nothing and had big losses the following years. 
Question: Which farm prevented more soil erosion?

A: Apple.
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Q: Background Paragraph: A wood-decay fungus is any species of fungus that digests moist wood, causing it to rot. Some species of wood-decay fungi attack dead wood, such as brown rot, and some, such as Armillaria (honey fungus), are parasitic and colonize living trees. Excessive moisture above the fibre saturation point in wood is required for fungal colonization and proliferation.[1] Fungi that not only grow on wood but permeate its fibrous structure and actually cause decay, are called lignicolous fungi. In nature, this process causes the breakdown of complex molecules and leads to the return of nutrients to the soil.[2] Various lignicolous fungi consume wood in various ways; for example, some attack the carbohydrates in wood and some others decay lignin. The rate of decay of wooden materials in various climates can be estimated by empirical models.[3]. 
Story: Bob is a botanist. His interest is in different kinds of fungi. He went to Brazil last month to study fungi in 
the Amazon rain forest. First day he searched for fungi in a location with excessive moisture. Second day he searched for fungi in a location with no moisture. In all his search he found two specimens of fungi. Specimen A is a brown rot fungus, and specimen B is a honey fungus. 
Question: Would specimen A fungus live on dead woods or not live on dead woods?

A: live on dead woods.
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Q: Background Paragraph: The water level is seasonal, being lowered by about 10 feet (3.0 m) over the winter. The reservoir fills in the spring from snow melt and underground springs. The lake is usually at full level by late spring, but in the occasional years of low snow melt and low rainfall, it may remain up to several feet below its typical level. Water is let out of the lake in the fall so that ice will not damage docks and other structures around the lake. This also leads to excellent water quality, as a significant portion of the water is replaced every year. 
Story: There are two hydroelectric dams in North Dakota. Both of them has large lakes or reservoirs, reservoir A and reservoir B. Since North Dakota has one the lowest unemployment rates in the country, it's hard to find an engineer to regulate and maintain the reservoirs. This year reservoir A could hire an engineer, but reservoir B failed to find an engineer. As a result, there is no one to regulate reservoir B. The engineer for reservoir A let the water out in the fall. But there was no one to do that for reservoir B. 
Question: Which reservior would most likely have excellent water quality, reservoir A or reservoir B?

A:
reservoir A.
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