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.

Example 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?
Example Output: Ural.

Example Input: Background Paragraph: Current Situation : Currently the heating effect of extra greenhouse gases (since the start of the industrial revolution) is equal to about . Thus the recent period has recorded parallel increases in concentration of carbon dioxide and average global temperature. As more greenhouse gases are put into the atmosphere the temperature will increase further. There are certain effects of a warmer Earth (discussed more in optional section), which could accelerate the process, even if no more greenhouse gases are put into the atmosphere (an unlikely prospect for the foreseeable future). 
Story: Last week, an exact clone of Earth appeared next to our current Earth. Scientists have come to call this new planet, Terra. Terra has the exact same cities, civilizations and history as Earth. Scientists are completely baffled as to how this planet exists, but it undeniably does. The only difference between Earth and Terra is that the citizens of Terra output half as many greenhouse gases into the atmosphere as citizens of Earth do. 
Question: Does Earth have more or less concentration of carbon dioxide than Terra?
Example Output: more.

Example Input: Background Paragraph: Clouds on Earth are made of water vapor. Venus's clouds are a lot less pleasant. They are made of carbon dioxide, sulfur dioxide and large amounts of corrosive sulfuric acid! The atmosphere of Venus is so thick that the pressure on the surface of Venus is very high. In fact, it is 90 times greater than the pressure at Earth’s surface! The thick atmosphere causes a strong greenhouse effect. As a result, Venus is the hottest planet. Even though it is farther from the Sun, Venus is much hotter even than Mercury. Temperatures at the surface reach 465°C (860°F). That’s hot enough to melt lead!. 
Story: In year 2200, David is an astronaut and an avid galaxy hopper from a planet hundred light years away. He ended up in the solar system in search of water. He identified three planets, planet A, planet B and planet C. Little did he know that less than a hundred years ago people used to call planet A as Earth, planet B as Venus, and planet C as Mercury. 
Question: Which planet would be cooler, planet B or planet C?
Example Output:
planet C.