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.
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Question: Background Paragraph: A baby is born with zones of cartilage in its bones that allow growth of the bones. These areas, called growth plates , allow the bones to grow longer as the child grows. By the time the child reaches an age of about 18 to 25 years, all of the cartilage in the growth plate has been replaced by bone. This stops the bone from growing any longer. Even though bones stop growing in length in early adulthood, they can continue to increase in thickness throughout life. This thickening occurs in response to strain from increased muscle activity and from weight-lifting exercises. 
Story: Two brothers, Tom, aged 26, and Paul, aged 16, started weight-lifting to gain more muscle mass. Three years later they were 20-25 lbs. heavier. 
Question: Which brother had active growth cartilages?

Answer: Paul.


Question: Background Paragraph: During the 1670s, the Dutch tradesman Antony van Leeuwenhoek, shown in Figure below , used microscopes to observe many microbes and body cells. Leeuwenhoek developed an interest in microscopy and ground his own lenses to make simple microscopes. Leeuwenhoek was so good at making lenses that his simple microscopes were able to magnify much more clearly than the compound microscopes of his day. His microscope's increased ability to magnify over 200x is comparable to a modern compound light microscope. Compound microscopes , which are microscopes that use more than one lens, had been invented around 1595 by Zacharias Jansen, a Dutch spectacle-maker. Several people, including Robert Hooke, had built compound microscopes and were making important discoveries with them during Leeuwenhoek’s time. 
Story: John is interested in the history of science. He went to a science museum to learn more about microscopes. First he saw a Leeuwenhoek microscope, which was labeled as item A, then he saw a compound microscope of Leeuwenhoek's time, which was labeled as item B. At the very end of his museum tour he saw a modern compound light microscope, which was labeled as item C. 
Question: Which one would have more lenses, item A or item B?

Answer: item B.


Question: Background Paragraph: Gasoline-powered vehicles emit a lot of harmful materials. Nitrogen oxides are formed when atmospheric nitrogen reacts with oxygen at the high temperatures found in a car engine. Carbon monoxide is a by-product of incomplete combustion of hydrocarbons. Evaporated and unused fuel releases volatile hydrocarbons into the atmosphere to help form smog. The presence of a catalytic converter in the exhaust system of the car causes these materials to react and be changed into less harmful products. 
Story: Bend village was located 20 miles away from Mound village. People in Bend village used gasoline powered vehicles, while Mound village used only electrical vehicles. 
Question: Which village emitted more harmful materials?

Answer:
Bend.