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: In exercises such as weight lifting, skeletal muscle contracts against a resisting force (see Figure below ). Using skeletal muscle in this way increases its size and strength. In exercises such as running, the cardiac muscle contracts faster and the heart pumps more blood. Using cardiac muscle in this way increases its strength and efficiency. Continued exercise is necessary to maintain bigger, stronger muscles. If you don’t use a muscle, it will get smaller and weaker—so use it or lose it. 
Story: Bill and Bob were two brothers. they were both into physical exercise, but Bill chose weight lifting, and Bob running. 
Question: Which brother used his cardiac muscle in a less efficient way?

Answer: Bill.


Question: Background Paragraph: One interesting thing that has been found in plants that are consistently exposed to drought, is their ability to form a sort of "memory". In a study by Tombesi et al., they found plants who had previously been exposed to drought were able to come up with a sort of strategy to minimize water loss and decrease water use. They found that plants who were exposed to drought conditions actually changed they way the regulated their stomates and what they called "hydraulic safety margin" so as to decrease the venerability of the plant. By changing the regulation of stomata and subsequently the transpiration, plants were able to function better in situations where the availability of water decreased. 
Story: Austria had two distinct climactic regions. The eastern region was exposed to a wet climate and had thriving vegetation, while the western region was exposed to drought. 
Question: Which region had more plants with an ability to change the way the regulated their stomates?

Answer: western.


Question: Background Paragraph: An anaerobic organism is any organism that does not need oxygen for growth and even dies in its presence. Obligate anaerobes will die when exposed to atmospheric levels of oxygen. Clostridium perfringens bacteria, which are commonly found in soil around the world, are obligate anaerobes. Infection of a wound by C. perfringens bacteria causes the disease gas gangrene. Obligate anaerobes use molecules other than oxygen as terminal electron acceptors. 
Story: Microbiologist John is studying the anaerobic organism. He collected two samples of this organism, sample A and sample B. Sample A is an anaerobic organism, and sample B is specifically identified as the Clostridium perfringens obligate anaerobe. To compare these samples to other organisms he collected another microbe that is not an anaerobic organism. He labeled it as sample C. 
Question: Which sample would need oxygen for growth, sample A or sample C?

Answer:
sample C.