Proponents of the Alvarez hypothesis hold that the impact of an astero

OFFICIAL EXPLANATION


THE PROMPT
• Issues

→ Idiom
In formal and academic writing, the verb hold often means "to espouse" or "to decide."

In this "reporting" context, the correct idiom is holds that.
The idiom is consistent with other reporting verbs followed by that, including believes that and states that.

→→ In Reynolds v. Sims (1964), the Supreme Court held that the Fourteenth Amendment's Equal Protection Clause required states to apportion voting districts for state legislatures according to the principle of "one person, one vote."

→→ "The Out of Africa theory holds that Homo sapiens burst onto the scene as a new species around 150,000 to 200,000 years ago in Africa and subsequently replaced archaic humans such as the Neandertals." Scientific American, here.

→ Parallelism and meaning
Parallelism is more than a grammatical formality.

It is also a conveyor of meaning or condition and result: in this case, parallel participles (verbING words) blocking and resulting differ from working verbs and convey the result of the impact of an asteroid crashing into earth.

Stated differently, "blocking sunlight" and "resulting in global cooling" are the results of the ejection of dust and so do not need to be parallel to ejection's verb (would have ejected)

THE OPTIONS

• meaning is a bit strange
→ the use of the word that after asteroid suggests that it was the asteroid (and not its crashing) that caused the ejection of the dust.
This issue is probably not enough on its own to eliminate the option because the ambiguity is subtle, but option A's ambiguity makes it inferior to option B, whose logic is clearer; in (B), the impact causes the ejection of the iridium dust

• lack of parallelism
→ blocked and resulting are not parallel

→ Blocking sunlight and resulting . . . in the halt of photosynthesis are results of the ejection of iridium dust.
COMMA + PRESENT PARTICIPLE (verbING) is one of GMAC writers' favorite ways to convey the result of the action or idea conveyed by the previous clause
ELIMINATE A

• I do not see any errors

• The sentence uses that after holds.

• blocking and resulting are parallel and properly so: (1) and is a parallelism marker, and (2) both are participles (___ING words) that are often used to describe results of the previous clause
KEEP

• the missing verb
→ The main sentence does not contain a working verb
→ The use of that before ejected eliminates the main verb from the sentence.
The relative pronoun that "eats up" the lone working verb, ejected

• what does that refer to? Earth? Probably not.
That probably refers to impact.
Almost always (99+% of the time), on the GMAT, that will define the immediately preceding noun.

SPOILER ALERT: The official question to which I link contains an exceptional construction.
On exceedingly rare occasions, short phrases intervene between a noun and its that-clause; an official question in which this construction occurs can be found here.
• the correct idiom is holds that
ELIMINATE C

• lack of parallelism
→ blocking and resulted are not parallel and should be so: both present outcomes of the ejected iridium dust

• the correct idiom is holds that
ELIMINATE D

• this sentence is a hot mess

• a case of the missing verb
→ AND would have ejected suggests a previous verb to which "would have ejected" should be paired, but no such verb exists

• meaning is silly
→ the impact [of the asteroid crashing into earth] caused the ejection of iridium dust, true
→ but that impact—the crash itself—did not block the sun or result in global cooling and darkness. The dust, not the crash, caused the blockage of the sun as well as the cold and darkness.
ELIMINATE E

The correct answer is B.

COMMENTS

Kyala1Jameson , welcome to SC Butler.

Everyone, thank you for your patience. It's been one of those weeks. I'll be playing catch-up for the next few days.

These answers range from very good to outstanding.

warrior1991 and Sumi1010 , I am bumping you both to Best Community Reply.
A couple of other posters came close to being bumped.
I will bump warrior1991 first; he is indeed a warrior. With seniority.

Nice work, everyone.

Proponents of the Alvarez hypothesis hold that the impact of an asteroid that crashed into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocked sunlight, and resulting in global cooling and a darkness that would have halted photosynthesis.

In this sentence
Cause: An asteroid that crashed into the earth would have ejected a tremendous amount of dust.
Effect: This dust would have blocked sunlight and resulted in global warming and a darkness.
To show cause and effect, comma+ing should be used.

A) that the impact of an asteroid that crashed into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocked sunlight, and resulting
ejected, blocked, and resulting are not parallel.

B) that the impact of an asteroid crashing into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocking sunlight and resulting
Correct

C) the impact of an asteroid crashing into earth that ejected a tremendous amount of iridium-containing dust into the atmosphere, blocking sunlight and resulting
This sentence non-sensically implies that the proponents hold the impact

D) the impact of an asteroid crashing into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocking sunlight and resulted
This sentence non-sensically implies that the proponents hold the impact

E) that the impact of an asteroid that crashed into earth and would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocked sunlight and resulted
The intended cause and effect is not implied in this sentence.

Choice B is the answer.

My answer is (B). It took me 01:07.

(A) from the shape of "X, Y, and Z", we expect to see parallels among "ejected", "blocked " and "resulting". They are not parallel in option (A).

(C) Proponents hold the impact? Does not make sense. (Note that "the impact of an asteroid crashing into earth that ejected a tremendous amount of iridium-containing dust into the atmosphere" is a noun phrase, not a subordinate clause, as in B).

(D) After hold, we need "that" to start a subordinate clause.

(E) In the subordinate clause introduced by "that", its subject is "the impact of an asteroid that crashed into earth and would have ejected a tremendous amount of iridium-containing dust into the atmosphere" and its main verb is "blocked sunlight and resulted...". There should be no comma between the subject and verb.

Proponents of the Alvarez hypothesis hold that the impact of an asteroid that crashed into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocked sunlight, and resulting in global cooling and a darkness that would have halted photosynthesis.


A) that the impact of an asteroid that crashed into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocked sunlight, and resulting
parallelism issue

B) that the impact of an asteroid crashing into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocking sunlight and resulting
error of A is adressed here

C) the impact of an asteroid crashing into earth that ejected a tremendous amount of iridium-containing dust into the atmosphere, blocking sunlight and resulting
that is missing

D) the impact of an asteroid crashing into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocking sunlight and resulted
that is missing

E) that the impact of an asteroid that crashed into earth and would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocked sunlight and resulted
tense error. effect is still persist

Its B

imo B

Proponents of the Alvarez hypothesis hold that the impact of an asteroid that crashed into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocked sunlight, and resulting in global cooling and a darkness that would have halted photosynthesis.


A) that the impact of an asteroid that crashed into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocked sunlight, and resulting
--Parallelism error ..

B) that the impact of an asteroid crashing into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocking sunlight and resulting
--Use of ,verbing correctly depicts the result of the previous clause

C) the impact of an asteroid crashing into earth that ejected a tremendous amount of iridium-containing dust into the atmosphere, blocking sunlight and resulting
-- Wrong modifier .. earth is not ejected

D) the impact of an asteroid crashing into earth would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocking sunlight and resulted
----Parallelism error ..



E) that the impact of an asteroid that crashed into earth and would have ejected a tremendous amount of iridium-containing dust into the atmosphere, blocked sunlight and resulted
-- meaning change error

The official explanation is here.

Hello from the GMAT Club VerbalBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.