Unlike using spices for cooking, in medicinal usage they are taken in large quantities in order to treat particular maladies.

A. Same
B. Unlike spices that are used in cooking, in using spices for medicine, they are taken
C. Unlike cooking with spices, taking spices for medicinal use is done
D. In cooking, small quantities of spices are used, whereas in medicinal usage spices are taken
E. In cooking, the usage of spices is in small quantities, whereas in medicinal usage they are taken

I chose E. Correct answer is D.
Now that I wrote this question I can see how maybe E is wrong because "they" is vague. Is that why it is incorrect? However, I still think E is better than D because there is parallelism of...I'm not sure if it's passive voice but the way the quantities (small/large) are described seem to better align itself in E than D. Please show me the error of my ways!

Following the Vertical Splits,
we have
1. Unlike Cooking
2. In Cooking.

A. Same..Incorrect
B. Unlike spices that are used in cooking, in using spices for medicine, they are taken
They are refers to what in the sentence? Eliminated
C. Unlike cooking with spices, taking spices for medicinal use is done
Incorrect.. taking spices..is done
D. In cooking, small quantities of spices are used, whereas in medicinal usage spices are taken
Correct.
E. In cooking, the usage of spices is in small quantities, whereas in medicinal usage they are taken
It is not parallelism here because the first part is usage of spices in small qnty while the second part is in passive voice. also it refers to they are taken which is what? Incorrect

Hence D

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