Astronomers have theorized that the Big Bang governs the behavior of interstellar dust, particles that comprise the atoms and molecules created in the progenitive explosion and persisting in even the emptiest regions of space.
(D) they persisted
(E) are persisting
Can you please advise why "are persisting" is wrong.
It's very important to understand the grammatical layout of the surrounding material. The words "interstellar dust
" is the object of the preposition "of
". The sentence could actually end there, and be a simple & complete sentence. Instead, we get an appositive phrase
", which modifies and describes the "interstellar dust
Then we have a "that
" clause, modifying "particles
" ---- it's a vital noun modifier
, because without the "that
" clause, the word "particles
" is pretty bland and undescriptive. Every "that
" clause must have a full SUBJECT + VERB structure. The pronoun "that
" itself is the subject, and comprise
is the verb. The nouns "atoms and molecules
" constitutes the direct object of comprise
The nouns "atoms and molecules
" is modified by one participial phrase
"created in the progenitive explosion
", and the question here poses --- what's going on with the "persist
" verb and the predicate that follows it?
" verb must take a form so that it is a second participle phrase parallel to the first. At the level of grammar, if we wanted to introduce more action here, something else doing the "persisting
" besides the "atoms and molecules
", then it would violate parallelism to have the first participle phrase, then the word "and
", and then something that's not a participial phrase. We would need more commas or something else to guide us if we wanted the "persist
" phrase to be parallel to something somewhere else in the sentence. At the level of logic, we are describing the origin & ongoing state of these "atoms and molecules
" ---- logically, it makes sense for the "persist
" phrase to be in parallel to the "created
Therefore, for a couple reasons, the second phrase must be a participle phrase in parallel to the first, and demands the participle "persisting
", not a full verb, such as "are persisting
Incidentally, this is not a very well written question. The word "progenitive
" is awfully fancy, a bit too fancy for GMAT SC standards. More importantly, the sentence misuses the word "comprise
" ---- a diction mistake the GMAT would never make.
I hope all this helps.
Magoosh Test Prep