54. Which is NOT CORRECT?
(A) Introduced species are sometimes a problem because they usually are better competitors.
(B) For carbon cycle, the CO2 would be returned to the atmosphere when the trees died and decayed.
(C) Global warming is caused by increased CO2 and CH4 levels.
(D) UV-B radiation is increasing due to increased CH4 concentration in the polar region.
(E) CO2 level increased due to enhanced human activities.
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統計: A(3), B(7), C(1), D(63), E(0) #2052905
統計: A(3), B(7), C(1), D(63), E(0) #2052905