题目内容：
根据下面材料，回答题Besides climate change，developing countries like China need to deal with energy _____21_____ and environmental issues：the development of sources of clean energy needs to be _____22_____ line with their interests．Clean energy has been given greater prominence than ever before；it is seen as a new industrial_____23_____and _____24_____ of economic growth for the new century．The time for clean energy has come．
In China．clean energy is moving ahead at full speed．Take wind power as an example：by the end of last year．China had_____25_____ wind power generating capacity of 12．21 GW，making China the largest wind power generator in Asia and first in the world．But according to the research，onethird of wind power capacity is running _____26_____ due to an inability to get the power to the national _____27_____．
India-like Cllinarelies____28______on coal for its energy needs．This will only change if the funds and technology to develop clean energy，such as wind and nuclear power，are____29______．India will not choose clean energy ____30______．Nuclear power is currently the most_____31_____of clean eftergy soulces．_____32_____．if it is to be _____33_____ on a large scale by developing nations，technological advances will be needed to make it competitive with coal．
Compared ______34____ developed countries，developing countries have more____35______choices when it comes to energy structure．Promoting economic growth requires____36______energy--and coal，the cheapest and most _____37_____ source of energy for many countries—is the _____38_____ choice．Cheap coal means cheap electricity and a competitive economy．Rising electricity prices would cause public ____39______and impact on standards of ____40______．
第21题答案为__________ A．scarce
B．scare
C．scarcity
D．scary
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