However at times this balance in nature is resulting in a number of possibly unforeseen e

问题补充：

However，at times this balance in nature is resulting in a number of possibly unforeseen effects.

A. troubled

B. disturbed

C. confused

D. puzzled

答案：

A. troubled

(答案→)B. disturbed

C. confused

D. puzzled

解析：词义辨析。A.麻烦； B.打乱； C.使困惑； D.使为难。句意：然而，有时自然平衡被打乱导致了大量可能无法预料的影响。故选B。