[Q]: The specialists studied two groups of larvae. Group L displayed all kinds of mutations while group D didn't. Which group of larvae had fewer hereditary diseases?
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[A]: group D

[Q]: John and Mary were studying insects. John liked to study insects that never eat, while Mary decided to study insects that are very healthy eaters. Which person studied more about moths?
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[A]: John

[Q]: Two sister cities had different environments. Shanghai had big problems with air pollution while Berna took very good care of the surrounding environment and air quality. Which city had air that was not harmful to other living things?
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[A]: Berna

[Q]: People from two villages got infected with viruses and got sick. People from Hill village got infected with the flu, while people in Valley village got infected with hepatitis B. Which villagers will not have the disease for life?
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[A]:
Hill