指代问题求教

wangwanwang

Whereas the use of synthetic fertilizers has greatly expanded agricultural productivity in many parts of 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.

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 substituion
E. the increased usage of these fertilizers can create serious environmental problems like water pollution, while their subsitution for more traditional fertilizers


正确选项是A 我知道其他选项的错误 可对A中an increase in their use...中their存在疑惑，这个their不会出现指代不明吗，因为前面既有parts 也有 synthetic fertilizers 啊，their不是就近指代parts吗还是说因为只有 synthetic fertilizers 在这里符合逻辑所以不会指代不明？？？那代词到底是就近指代呢还是说先看逻辑关系，十分迷惑，求解答，谢谢谢谢

wangwanwang

么人，自己顶

wangwanwang

咋还没人啊，顶顶顶