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
D的错误 1. increased usage应该用increased use 2. whereas..., while if...错误,这两个连词差不多,正常用法都是whereas... , ...或... whereas.../ while... , ...或 ... while ...表转折,只能用一个,否则就好像说,although i am fat, but i am quick一样的错误 3. 后部分逻辑主语有问题。 while (synthetic fertilizers are) substituted..., the substitution...这个应该不是主语重复,而是逻辑主语不对吧