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.

[EX Q]: 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 4th grade classroom photo was held today. They all gathered by age. Ahmed was the oldest. Jefferey was the 2nd oldest. Tyree was the 3rd oldest. Walker was the 4th oldest. Burl was the 5th oldest. Kip was the 6th oldest. The last one was Quinn, who was the youngest. They all looked wonderful that day. 
Question: Who has a greater chance of developing a chronic infection: Walker or Kip?
[EX A]: Kip.

[EX Q]: Background Paragraph: Boys and girls between the ages of 9 and 13 should get 9 mg of iron every day. Girls between the ages of 14 and 18 should get 15 mg of iron every day. Boys between the ages of 14 and 18 should get 11 mg of iron every day. Pregnant women need the most iron—27 mg daily. Good sources of iron include shellfish, such as clams and oysters. Red meats, such as beef, are also a good source of iron. Non-animal sources of iron include seeds, nuts, and legumes. Breakfast cereals often have iron added to them in a process called fortification. Some good sources of iron are listed below ( Table below ). Eating vitamin C along with iron-containing food increases the amount of iron that the body can absorb. 
Story: David works as a nutritionist with the public health department. He categorized the certain sections of his county's population. First he categorized boys and girls between nine and thirteen years as cat A. Then he put girls between fourteen and eighteen years in cat B, and boys of the same age in cat C. Lastly, he categorized pregnant women as cat D. He needs to recommend healthy diet, especially iron intake, for each group. 
Question: Which group would need more iron, cat B or cat C?
[EX A]: cat B.

[EX Q]: Background Paragraph: Water stratification is when water masses with different properties - salinity (halocline), oxygenation (chemocline), density (pycnocline), temperature (thermocline) - form layers that act as barriers to water mixing which could lead to anoxia or euxinia.[1] These layers are normally arranged according to density, with the least dense water masses sitting above the more dense layers.

Water stratification also creates barriers to nutrient mixing between layers. This can affect the primary production in an area by limiting photosynthetic processes. When nutrients from the benthos cannot travel up into the photic zone, phytoplankton may be limited by nutrient availability. Lower primary production also leads to lower net productivity in waters.[2]. 
Story: High lake had a lot of fresh and salt water mixing, therefore presented layers of stratified water.The water was poor in nutrients.Low lake had no such problems and it was a very abundant and prolific fishing spot. 
Question: Which lake had fewer dissolved nutrients?
[EX A]:
High lake.