GMAT Sentence Correction (SC) | Re: Not only did the systematic clearing of forests in the

Not only But Also construction is used when one talks about one extreme end of a thing for example air pollution not only effected population health but also effected plants and animals health.....negative impact of air pollution not only x but also y
Over here the question says that systematic clearing of forest if gives inexpensive houses, it also promote erosion...so one positive impact and other is negative impact. Therefore, one can rule out A and B.
C is not even a proper sentence
E is wrong
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