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: Compared to conventional milk production, organic milk production tends to have lower eutrophication potential per ton of milk or per hectare of farmland, because it potentially reduces leaching of nitrates (NO3−) and phosphates (PO4−) due to lower fertilizer application rates. Because organic milk production reduces pesticides utilization, it increases land use per ton of milk due to decreased crop yields per hectare. Mainly due to the lower level of concentrates given to cows in organic herds, organic dairy farms generally produce less milk per cow than conventional dairy farms. Because of the increased use of roughage and the, on-average, lower milk production level per cow, some research has connected organic milk production with increases in the emission of methane.Animal welfare issues vary among dairy farms and are not necessarily related to the way of producing milk (organically or conventionally). 
Story: There are two dairy farms in the town of Milkton and both are about the same size. Farm A produces only organic milk. Farm B does not but they are considering switching production to organic milk. 
Question: Which farm likely has higher milk yields, farm A or B?
[A]: B.


[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: Twenty first century is seeing an explosion of artificial island building. Many countries are building islands in the middle of seas and oceans, which they often use for tourism or for defensive purposes. For example, UAE had build several islands in the Persian Gulf. To build those islands they had to ask Oman and Qatar to export sand to them. Qatar declined to export sand, but Oman agreed. Oman in turn had to mine huge quantity of sand in their own country. 
Question: Would Oman remove or retain their coaster barriers?
[A]: remove.


[Q]: Background Paragraph: Reduction of the area of Arctic sea ice reduces the planet's average albedo, possibly resulting in global warming in a positive feedback mechanism. Research shows that the Arctic may become ice free in the summer for the first time in human history within by 2040. Estimates vary for when the last time the Arctic was ice free: 65 million years ago when fossils indicate that plants existed there to as few as 5,500 years ago; ice and ocean cores going back 8000 years to the last warm period or 125,000 during the last intraglacial period.Warming temperatures in the Arctic may cause large amounts of fresh meltwater to enter the north Atlantic, possibly disrupting global ocean current patterns. Potentially severe changes in the Earth's climate might then ensue.As the extent of sea ice diminishes and sea level rises, the effect of storms such as the Great Arctic Cyclone of 2012 on open water increases, as does possible salt-water damage to vegetation on shore at locations such as the Mackenzie's river delta as stronger storm surges become more likely.Global warming has increased encounters between polar bears and humans. Reduced sea ice due to melting is causing polar bears to search for new sources of food. Beginning in December 2018 and coming to an apex in February 2019, a mass invasion of polar bears into the archipelago of Novaya Zemlya caused local authorities to declare a state of emergency. Dozens of polar bears were seen entering homes and public buildings and inhabited areas. 
Story: Mike was reading about climate change. The author compared two different time periods, era A and era B. Era A was set in the present day. But era B was set in the year 2040. Mike was surprised to find how Arctic area would change in the coming years. 
Question: Which period would see less human polar bear encounters, era A or era B?
[A]:
era A.