GMAT Sentence Correction (SC) | Re: In early Mesopotamian civilization, castor oil served not only as a la

In early Mesopotamian civilization, castor oil servednot only as a laxative, but also a skin-softening lotion and it was a construction lubricant for sliding giant stone blocks over wooden rollers.

A.not only as a laxative, but also a skin-softening lotion andit was a construction
- In order to maintain Parallelism, 2nd item for BUT ALSO has to be a Noun and not a clause. Hence Incorrect B.as not only a laxative, but also a skin-softening lotion, andit was a construction
- In order to maintain Parallelism,
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