Problem:OPTIONS:
- cellulose
- Species
- orchids
- the sun
- h2o
- organisms
- glass
- our planet

You are presented with the quiz "what is a greenhouse used to protect?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "agreenhouse is used to protect plants by keeping them warm" and "many orchids are rewarding indoor plants". So, what's the best answer to the question?
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A: orchids

Problem:OPTIONS:
- Acids
- tar
- Energy.
- heat
- Gases
- gas
- sweat
- energy

You are presented with the quiz "What does an automobile create when it burns fuel?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "operating an automobile usually requires fossil fuels" and "automobiles and the burning of fossil fuels generate gases such as sulphur dioxide". So, what's the best answer to the question?
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A: Gases

Problem:OPTIONS:
- the oak can get wider
- at or near the margins
- the oak can fall
- the oak can stay in place
- competing for resources
- hydrogen and oxygen
- the oak can get taller
- by indirect light

You are presented with the quiz "How can sunlight get to plants surrounding an oak?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "if a tree falls then sunlight becomes available to the surrounding plants" and "all oaks are trees". So, what's the best answer to the question?
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A: the oak can fall

Problem:OPTIONS:
- life
- Inheriting genes
- security
- smoking tobacco
- electromagnetic energy
- safety
- heat or cold
- Destroy bridges

You are presented with the quiz "What can kill?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "cancer genes can be inherited" and "breast cancer kills". So, what's the best answer to the question?
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A:
Inheriting genes