In a large forest with many animals, there are only a small number of bears. Which of these most likely limits the population of bears in the forest?
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OPTIONS:
- supply of food
- type of tree
- predation by carnivores
- amount of suitable shelter

supply of food

Scurvy is a disease that sailors often got on long voyages. It was discovered that scurvy could be prevented by eating oranges and lemons. This suggests that scurvy is a disease caused by
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OPTIONS:
- exposure to sea air
- a nutritional deficiency
- a microorganism
- lack of exercise

a nutritional deficiency

Which is a nonrenewable natural resource that is used to make electrical energy?
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OPTIONS:
- coal
- wind
- water
- thermal
coal