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.

Input: Consider Input: Background Paragraph: About 10% of sedimentary rocks are limestones. The solubility of limestone in water and weak acid solutions leads to karst landscapes, in which water erodes the limestone over thousands to millions of years. Most cave systems are through limestone bedrock.
Story: White mountains are often visited by tourists because of the many beautiful caves, stalactites, stalagmites and karst phenomena. Dome mountains are interesting to tourists because they are very massive, of volcanic origin and excellent for climbing.
Question: Which mountain is made of less soluble rock?

Output: Dome.

Input: Consider Input: Background Paragraph: Noble gases are also used to fill the glass tubes of lighted signs like the one in the Figure below . Although noble gases are chemically nonreactive, their electrons can be energized by sending an electric current through them. When this happens, the electrons jump to a higher energy level. When the electrons return to their original energy level, they give off energy as light. Different noble gases give off light of different colors. Neon gives off reddish-orange light, like the word "Open" in the sign below. Krypton gives off violet light and xenon gives off blue light.
Story: Bob owns a store that sells signs. He has a large selection of different signs that are for sale, and they come in all sorts of different colors. His closed sign is a reddish-orange. His open sign is a violet color, and his sale sign is blue.
Question: Which sign in Bob's store uses Neon gas?

Output: closed sign.

Input: Consider Input: 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?
Output: remove.