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.

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 2nd grade classroom photo was held today. They all gathered by age. Foster was the oldest. Olin was the 2nd oldest. Yong was the 3rd oldest. Brenton was the 4th oldest. Carol was the 5th oldest. Dewitt was the 6th oldest. The last one was Jamaal, who was the youngest. They all looked terrific that day. 
Question: Who has a greater chance of developing a chronic infection: Foster or Dewitt?
Dewitt.

Background Paragraph: During Amniocentesis a small amount of amniotic fluid, which contains fetal cells, is extracted from the amnion or amniotic sac surrounding a developing fetus, and the fetal DNA is examined for genetic abnormalities. Amniocentesis is not performed for every pregnancy, but is generally done when an increased risk of genetic defects in the fetus is indicated, by mother's age (over 35 years is common), family history of genetic defects, or other factors. 
Story: David is a doctor with the city hospital. Today, he is seeing four patients, patient A, patient B, patient C, and patient D. All four patients are expectant mothers. Moreover, patient A is over thirty five years old, but patient B is under thirty five years old. Patient C has family history of genetic disorder, but patient D does not have any family history of genetic disorder. David needs to prescribe appropriate treatment according to each patient's condition. 
Question: Would patient A be less or more at risk of genetic defects in the fetus than patient B?
more.

Background Paragraph: Animals and some bacteria and fungi carry out lactic acid fermentation. Lactic acid is a waste product of this process. Our muscles perform lactic acid fermentation during strenuous exercise, since oxygen cannot be delivered to the muscles quickly enough. The buildup of lactic acid is believed to make your muscles sore after exercise. Bacteria that produce lactic acid are used to make cheese and yogurt. The lactic acid causes the proteins in milk to thicken. Lactic acid also causes tooth decay, because bacteria use the sugars in your mouth for energy. 
Story: Mark and Jerry are brothers. Mark just got done working out and returned home to find his brother laying down on the couch eating a bag of potato chips. Mark comments that Jerry should really come and work out with him some time. Jerry brushes him aside. 
Question: Which person's body has less lactic acid?

Jerry.