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.

Ex Input:
Background Paragraph: Plucking, also referred to as quarrying, is a glacial phenomenon that is responsible for the erosion and transportation of individual pieces of bedrock, especially large "joint blocks". This occurs in a type of glacier called a "valley glacier". As a glacier moves down a valley, friction causes the basal ice of the glacier to melt and infiltrate joints (cracks) in the bedrock. The freezing and thawing action of the ice enlarges, widens, or causes further cracks in the bedrock as it changes volume across the ice/water phase transition (a form of hydraulic wedging), gradually loosening the rock between the joints. This produces large pieces of rock called joint blocks. Eventually these joint blocks come loose and become trapped in the glacier. 
Story: Rob likes to visit high mountainous locations. Last year he visited the the Alps mountains in Austria. There he saw an unique type of glacier called valley glacier. This year he went further east to visit the Ural mountains in Russia. There he didn't see any valley glacier. 
Question: Which mountain would not see erosion of bedrocks?

Ex Output:
Ural.


Ex Input:
Background Paragraph: Something that is elastic can return to its original shape after being stretched or compressed. This property is called elasticity . As you stretch or compress an elastic material like a bungee cord, it resists the change in shape. It exerts a counter force in the opposite direction. This force is called elastic force . The farther the material is stretched or compressed, the greater the elastic force becomes. As soon as the stretching or compressing force is released, elastic force causes the material to spring back to its original shape. You can watch a demonstration of elastic force at this URL:. 
Story: Andy is playing with a rubber band. He stretches the rubber band out as far as he can without breaking it. 
Question: Will the amount of force required to stretch the rubber band increase or decrease as he stretched it further?

Ex Output:
increase.


Ex Input:
Background Paragraph: Rain dissolves fertilizer in the soil. Runoff carries it away. The fertilizer ends up in bodies of water, from ponds to oceans. Nitrogen is a fertilizer in the water. Since there is a lot of nitrogen, it causes algae to grow out of control. Pictured below is a pond covered with algae ( Figure below ). Algae use up carbon dioxide in the water. After the algae die, decomposers break down the dead tissue. The decomposers use up all the oxygen in the water. This creates a dead zone. A dead zone is an area in a body of water where nothing grows because there is too little oxygen. There is a large dead zone in the Gulf of Mexico ( Figure below ). The U.S. states outlined on the map have rivers that drain into the Gulf of Mexico. The rivers drain vast agricultural lands. The water carries fertilizer from these areas into the Gulf. 
Story: Park farm and Fiddle farm provided Red city with tonnes of produce annually. Fiddle farm used and abundance of fertilizers and pesticides, while Park farm didn't use any of those substances. 
Question: Which farm caused less fertilizer to dissolve in the soil because of rain?

Ex Output:

Park.