A. Peat
B. Crude Oil
C. Natural gas
D. Tar sands
参考答案:
A
本题详细解析:
Explanation:
When soil is waterlogged, anaerobic conditions can develop and the soil sometimes becomes acidic. In these conditions, partially decomposed organic matter will form peat.
Crude oil is formed when organic matter buried deep in the earth is compressed by pressure and heat over millions of years. (Choice B)
Natural gas (Choice C) is found in underground shale formations and sandstone beds. Tar sand is a mix of sand, clay, water and bitumen (used for road surfacing) (Choice D).
