Hello Everyone!
Let's take a look at this question, and figure out how to get to the correct answer quickly! Here is the original question, with any major differences between each answer highlighted in
orange:
Researchers now regard interferon
as not a single substance, but it is rather a biological family of complex molecules that play an important, though not entirely defined, role in the immune system.
A.
as not a single substance,
but it is rather a biological family of complex molecules
that playB.
as not a single substance
but as a biological family of complex molecules
playingC.
not as a single substance
but as a biological family of complex molecules
that playD.
not to be a single substance
but rather a biological family of complex molecules
playingE.
not as a single substance
but instead as being a biological family of complex molecules
that playAfter glancing over the major differences between each answer, one thing pops out right away: parallelism! We have two items we're dealing with: a single substance & a biological family of complex molecules. To make this sentence sound clear and correct, it's best to use parallel structure to refer to both items. So let's see which answers use parallel structure, and eliminate those that don't.
A.
as not a single substance, but
it is rather a biological family of complex molecules that play -->
WRONG / NOT PARALLEL (For this to be parallel, it would need to say "as not
a single substance, but
a biological family."
B.
as not a single substance
but as a biological family of complex molecules playing -->
WRONG / NOT PARALLEL(Again, for this to be parallel, it would need to say "as not
a single substance but
a biological family."
C.
not as a single substance
but as a biological family of complex molecules that play -->
CORRECT / PARALLEL(This uses parallel structure to start both phrases by beginning both with the words "as a...")
D.
not to be a single substance
but rather a biological family of complex molecules playing -->
WRONG / NOT PARALLEL(For this to be parallel, it would need to say "not
to be a single substance, but
to be a biological family...")
E.
not as a single substance
but instead as being a biological family of complex molecules that play -->
WRONG / NOT PARALLEL(For this to be parallel, it would need to say "not
as a single substance, but as a biological family...")
Well there you have it!
Option C is the correct answer because it is the only answer that uses parallel structure!Don't study for the GMAT. Train for it.