instruction:
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.
question:
Background Paragraph: One of the most adverse impacts of poor waste management, especially municipal waste, is the incidence and prevalence of diseases such as malaria and respiratory problems, as well as other illnesses through the contamination of ground water. Biomedical wastes pose great danger in Bangladesh too as a report estimated that 20% of the biomedical waste is "highly infectious" and is a hazard since it is often disposed of into the sewage system or drains.[6]  Such poor sanitation has serious consequences for the health of the residents and a report suggests that "most of the child mortality could be related with this problem".[7]  With regards to the living standards, solid waste leads to blockage in the drainage system which leads to flooding in the streets. Consequently, mosquitoes and bad odour are among the negative impacts resulted.[7]. 
Story: Calgary has just installed a new waste management system in the city, and has been writing new laws about how biomedical research should be properly disposed of. Detroit on the other hand, just passed a law that allows dumping of medical waste in the sewage system, and has cut funding to it's waste management system. 
Question: Which city probably has a lower chance of contaminated ground water?
answer:
Calgary.


question:
Background Paragraph: Air pollution is harmful to human beings and other living things. About 22 million people die from air pollution each year. Breathing polluted air increases the risk of developing lung diseases such as asthma and lung cancer. Breathing bad air also increases the chances of dying from other diseases. Children are most likely to be affected by air pollution. That’s because their lungs are still developing and growing. Children also take in more air for their size than adults do. Some air pollutants damage the environment as well as the health of living things. The type of damage depends on the pollutant. Air pollution can also harm the environment. 
Story: Manny visited 2 countries. First he visited Australia, a country which respected the environment and produced zero air pollution, and New Zealand, a country which based its economy on burning fossil fuels and generated a lot of air pollution. 
Question: Which country had less environmental damage because of air pollution?
answer:
Australia.


question:
Background Paragraph: Retinitis is inflammation of the retina in the eye, which can permanently damage the retina and lead to blindness. The retina is the part of your eye that is also known as the "sensing tissue." Retinitis may be caused by a number of different infectious agents. Retinitis, also called Retinitis pigmentosa, has a prevalence of one in every 2,500-7,000 people. This condition is one of the leading causes that leads to blindness in patients in the age range of 20–60 years old. 
Story: Local hospital has launched a program to check if a patient has Retinitis. Resident ophthalmologist David is in charge of this program. In the first day of the program he checked two patients, patient A and patient B. The test result showed that patient A had Retinitis, but patient B did not have Retinitis. Then next day 
David checked two other patients, patient C and patient D. Patient C was 40 years old, but patient D was 80 years old. He found both patient C and D had Retinitis. 
Question: Which patient is in risk of becoming blind, patient A or patient B?
answer:

patient A.