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: Arbuscular mycorrhizal fungi vary across many environmental gradients. Their tolerance to freezing and drying is known to shift between AM fungal taxa. AM fungi become less prevalent and diverse at higher soil nutrient and moisture concentrations, presumably because both plants allocate less carbon to AM fungi and AM fungi reallocate their resources to intraradical hyphae in these environmental conditions. Over the long term, these environmental conditions can even create local adaptation between plant hosts, AM fungi and the local soil nutrient concentrations. 
Story: Hill town had two large forests nearby. Lake forest had trees that were in a symbiotic relationship with a large variety of arbuscular mycorrhizal fungi. These fungi were less prevalent  in Brook forest. 
Question: Which forest had a higher soil moisture concentration?

A: Brook.
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Q: Background Paragraph: Using longitudinal data from over 100 countries, Diener and his colleagues showed that rich countries are in general happier than poor countries (Diener, Tay, & Oishi, 2013).[17] Also, life satisfaction for most countries goes up as they become wealthier over time. Diener identified three factors that influence the relationship between income and SWB. Namely, rising income most likely results in higher SWB when it leads to greater optimism, financial satisfaction and household material prosperity among citizens. Furthermore, Diener and his colleagues investigated the relationship between income and different elements of SWB. They illustrated that income has stronger influence on people’s evaluation of their lives than the positive or negative emotions they experience over time (Diener, Kahneman, Tov, & Arora, 2010).[18] The study points to the necessity to evaluate different elements of SWB separately instead of treating happiness as a single entity. 
Story: Over the years, the town of Euphoria has grown more successful and wealthier than anyone ever thought. As the wealth has increased and people have acquired more material possessions, their outlook on life has become more positive and it has been noted that the citizens have a lower incidence of depression. The town of Zenphora, on the other hand, has taken a downward financial turn over the past 50 years. The citizens have had to sell their worldly goods just to make ends meet and many do not have a good feeling about what their future holds. 
Question: If the financial situation in Euphoria decreases will the SWB increase or decrease?

A: decrease.
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Q: Background Paragraph: Sand mining is a direct cause of erosion, and impacts the local wildlife.[2] Various animals depend on sandy beaches for nesting clutches, and mining has led to the near extinction of gharials (a species of crocodile) in India. Disturbance of underwater and coastal sand causes turbidity in the water, which is harmful for organisms like coral that need sunlight. It can also destroy fisheries, financially harming their operators.

Removal of physical coastal barriers, such as dunes, sometimes leads to flooding of beachside communities, and the destruction of picturesque beaches causes tourism to dissipate. Sand mining is regulated by law in many places, but is often done illegally.[3] Globally, it is a $70 billion industry, with sand selling at up to $90 per cubic yard.[4]. 
Story: Sand mining in the north coastal region was stopped 20 years ago, but it still continues to this day in the south region. Both fishing communities there are still prosperous, but the southern one had a couple of bad years, with fish and other marine wildlife becoming more scarce. The southern beach had erosion problems as well. The northern beach recovered, and is suitable for tourism. 
Question: Which region has a more coral riffs?

A:
northern.
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