Whereas the use of synthetic fertilizers has greatly expanded agricultural productivity in many partsof the world, an increase in their use can create serious environmental problems such as water pollution, and their substitution for more traditional fertilizers may accelerate soil structure

deterioration and soil erosion.

(A) an increase in their use can create serious environmental problems such as water pollution, and  their substitution for more traditional fertilizers

(B) an increase in their use can create serious environmental problems like water pollution, and if substituted for more traditional fertilizers, it

(C) if these fertilizers are used increasingly, they can create serious environmental problems such  as water pollution, and if used as substitutions for more traditional fertilizers, they

(D) the increased usage of these fertilizers can create serious environmental problems such as water pollution, while if substituted for more traditional fertilizers, this substitution

(E) the increased usage of these fertilizers can create serious environmental problems like water pollution, while their substitution for more traditional fertilizers


答案是A，我错选了C，当时想C比A要对称一致呢。。。求解释求解释，谢谢各位