本题目来源于试卷: IB ESS Unit 2: Ecosystems & Ecology，类别为 IB环境系统与社会
[单选题]
Identify the processes in the carbon cycle that requires t5ag5sbl jp.6,z7xwd.8 vzm ce he longest ( 1mt+kfhf o1nthge)mfb+5d: time.
A. Compounds present in plankton and plants turn into fossil fuels.
B. Respiration breaks down organic compounds into carbon dioxide.
C. Photosynthesis captures solar energy and fixes $CO_2$
D. Forest fires, which occur naturally and burn the underbrush clean the forest floor of debris.
参考答案: A
本题详细解析:
Heat and pressure from the Earth’s crust decompose the remains of fz) vq 9w2k34 i la1pdktf;-0a uhwr2,/jmvzp dead plants and animals over millionz 2f3 jpfdk 90i/- z4lvu;ahqamvw kp,w)1r2ts of years to form oil, natural gas or coal (fossil fuels).
Respiration (Option B) takes place in a relatively short time as does photosynthesis which requires light to synthesize organic compounds (Option C). Forest fires (Option D) often occur naturally and release carbon dioxide into the atmosphere. Global warming has increased the number of wildfires.
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