Hello Everyone!
Let's take a close look at this question, one problem at a time, to come up with the right answer quickly! Before we dive in, here is the original question with the major differences between each option highlighted in
orange:
The intricate structure of the compound insect eye,
having hundreds of miniature eyes called ommatidia, help explain why scientists have assumed that it evolved independently of the vertebrate eye.
(A)
having hundreds of miniature eyes called ommatidia,
help explain why scientists have assumed that
it(B)
having hundreds of miniature eyes that are called ommatidia,
helps explain why scientists have assumed that
they(C)
with its hundreds of miniature eyes that are called ommatidia,
helps explain scientists' assuming that
they(D)
with its hundreds of miniature eyes called ommatidia,
help explain scientists' assuming that
it(E)
with its hundreds of miniature eyes called ommatidia,
helps explain why scientists have assumed that
itRight away, 3 major differences jump out between each option:
1. having hundreds / with its hundreds
2. help / helps
3. it / they#2 and #3 on the list are both easy concepts to deal with, so let's start there before getting to #1 on the list, which is a little more complicated.
#2 on our list deals with
subject/verb agreement. We know that the subject is the singular word "structure." Let's rule out any options that use the plural verb "help," which doesn't agree in number with our singular subject!
(A) having hundreds of miniature eyes called ommatidia,
help explain why scientists have assumed that it
(B) having hundreds of miniature eyes that are called ommatidia,
helps explain why scientists have assumed that they
(C) with its hundreds of miniature eyes that are called ommatidia,
helps explain scientists' assuming that they
(D) with its hundreds of miniature eyes called ommatidia,
help explain scientists' assuming that it
(E) with its hundreds of miniature eyes called ommatidia,
helps explain why scientists have assumed that it
There you go - right away,
we can eliminate options A & D because they don't follow proper subject/verb agreement! Now, let's tackle #3 on our list: it/they. This is an issue of
pronoun/antecedent agreement! The pronouns are referring back again to our subject: structure. Let's rule out any options that use the plural pronoun "they" because it doesn't agree in number with our singular antecedent:
(B) having hundreds of miniature eyes that are called ommatidia, helps explain why scientists have assumed that
they(C) with its hundreds of miniature eyes that are called ommatidia, helps explain scientists' assuming that
they(E) with its hundreds of miniature eyes called ommatidia, helps explain why scientists have assumed that
itThis leaves us with only one option left - option E, which is the correct answer! It uses proper subject/verb agreement and pronoun/antecedent agreement throughout!
(If you're wondering why we skipped over #1 on our list, it's because both constructions are actually okay to use. Instead of wasting time fretting over something that looks confusing, start with the easy differences first, such as subject/verb agreement or pronoun/antecedent agreement. Most of the time, those will rule out enough options for you to choose the correct overall answer. If not, then you can take more time to deal with the more complicated stuff.)Don't study for the GMAT. Train for it.
_________________
EMPOWERgmat
Total GMAT Content & Tactical Training | 120 Point Guarantee | All 6 Official GMAT Tests
empowergmat.com