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: Hepatitis B is a contagious virus that affects the liver, infection can last from a few weeks to a serious lifelong illness. Two different types of infection exist for this disease, "acute" and "chronic." Acute Hepatitis B is a short term illness that occurs within 6 months of exposure, Chronic Hepatitis B is long term and happens when the virus remains in the body. The younger the child is, the greater their chance of developing a chronic infection and this risk goes down as the child gets older. Approximately 90% of infected infants will develop a chronic infection.[3]. 
Story: A 3rd grade classroom photo was held today. They all gathered by age. Lenny was the youngest. Connie was the 2nd youngest. Newton was the 3rd youngest. Amado was the 4th youngest. Dillon was the 5th youngest. Thanh was the 6th youngest. The last one was Frances, who was the oldest. They all looked great. 
Question: Who has a greater chance of developing a chronic infection: Thanh or Lenny?

Answer: Lenny.


Question: Background Paragraph: Regions on the Earth's surface (or in its atmosphere) that are high above mean sea level are referred to as high altitude. High altitude is sometimes defined to begin at 2,400 meters (8,000 ft) above sea level.[5][6][7]

At high altitude, atmospheric pressure is lower than that at sea level. This is due to two competing physical effects: gravity, which causes the air to be as close as possible to the ground; and the heat content of the air, which causes the molecules to bounce off each other and expand.[8]. 
Story: Riley has just been diagnosed with a disease that requires him to be in an area that has low atmospheric pressure to help his breathing. He has two cities he can choose to live in based on his current budget. Denver with an elevation of 10,000 ft, and Miami, which is around sea level. 
Question: What city should Riley avoid moving to because it will most likely have higher atmospheric pressure?

Answer: Miami.


Question: Background Paragraph: Matter, dark matter, and dark energy are distributed homogeneously throughout the Universe over length scales longer than 300 million light-years or so. However, over shorter length-scales, matter tends to clump hierarchically; many atoms are condensed into stars, most stars into galaxies, most galaxies into clusters, superclusters and, finally, large-scale galactic filaments. The observable Universe contains approximately 300 sextillion (3×1023) stars and more than 100 billion (1011) galaxies. Typical galaxies range from dwarfs with as few as ten million (107) stars up to giants with one trillion (1012) stars. Between the larger structures are voids, which are typically 10–150 Mpc (33 million–490 million ly) in diameter. The Milky Way is in the Local Group of galaxies, which in turn is in the Laniakea Supercluster. This supercluster spans over 500 million light-years, while the Local Group spans over 10 million light-years. The Universe also has vast regions of relative emptiness; the largest known void measures 1.8 billion ly (550 Mpc) across. 
Story: Rob is an amateur astronomer. He was looking at the sky with his telescope. First he took a longer length observation. He noted his observation as case A. Then he took a shorter length observation. He noted that observation as case B. He found that it's beneficial to take both observations to get a fuller view of the observable universe. 
Question: Which observation would not detect stars and galaxies well, case A or case B?

Answer:
case A.