单项选择题

The passage states that _______.

A．many Americans have switched from hydrocarbon-based fuels to wood because the price of the latter has risen.
B．some wood-burning stoves cost up to one hundred times more than others.
C．catalytic combustors increase the amount of pollution caused by wood burning stoves.
D．agitators are cheaper addition to wood-burning stoves than catalytic combustors.

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热门试题

单项选择题

Which of the following statements is NOT true

A．Wood-burning stoves are safer and more efficient than they used to be.
B．No factories exist for the purpose of producing dirty wood chips.
C．Both catalytic combustors and wood agitators save money in the long run.
D．Wood-burning stoves with catalytic combustors cost between $100 and $ 200.

单项选择题

Which one of the following is NOT true for the reason why people prefer to buy wood-burning stoves

A．The initial cost is very low.
B．The fuel costs are cheaper.
C．Wood fires are more efficient, cleaner, and safer than ever before.
D．The wood-burning stoves are more efficient than gas or oil ones.