Migraine, the most debilitating common form of headache, afflicts

good question and i know you are intimited by the migrain.
the subject of the verb "cost" is not migrain.
the subject is "who". who refers to those migrain afflicted 18 mil people.

(A) year, and they cost the nation $50 billion in medical expenses and lost - Wrong: 1) Pronoun Ambiguity 2) Parallelism issue

(B) year and thus cost the nation $50 billion in medical expenses and lost - Correct

(C) year, so as to cost the nation $50 billion in medical expenses and lost - Wrong: 1) Meaning issue

(D) year that costs the nation $50 billion in lost medical expenses and - Wrong: 2 modifier issues

(E) year, which thus cost the nation $50 billion in lost medical expenses and - Wrong: 2 modifier issues

This question just seems pretty off in terms of meaning. Fundamentally, it is the disease that costs the nation money and lost workday, not the people. The correct answer C's meaning seems off. Honestly, I feel like "so as to" kinda works, but it involves too much about intention/purpose, which is not what the disease is intentionally doing.

Migraine, the most debilitating common form of headache, afflicts perhaps 18 million Americans, who collectively lose 64 million workdays a year, and they cost the nation $50 billion in medical expenses and lost work time.

Meaning Analysis: Migraine (which is a common form of headache) affects 18M Americans. These "affected" Americans lose 64 million work days and as a result of them losing so many work days, they cost the nation $50 billion in the form of (1) medical expenses and (2) work time that they lose out on

Sentence structure:

Migraine (Subject)
,the most debilitating common form of headache, (Modifier modifying the noun "Migraine") (notice the modifier is in a COMMA PAIR)
afflicts (Verb)
perhaps 18 million Americans (modifier - gives additional information about the verb)
,who collectively lose 64 million workdays a year, (Relative noun modifier modifying "Americans") (DC - "who" Subject ; "lose" - Verb)
and (Parallelism marker)
they (Subject)
cost (Verb)
the nation $50 billion in medical expenses (Additional information about cost)
and (parallelism marker)
lost work time. (second entity of the parallel list)

Error Analysis:

(A) year, and they cost the nation $50 billion in medical expenses and lost - Incorrect We want to convey that due to the loss of 64 million work days the nation incurs $50B. But by starting an IC we are conveying two separate ideas. This sentence now conveys that
(1) The 18M affected Americans lose 64M word days and
(2) the 18M affected Americans cost the nation $50B.

As we can see, the intended "cause and effect" relationship is not correctly conveyed

B) year and thus cost the nation $50 billion in medical expenses and lost - Correct By using "thus" we are stating the result of "the loss of 64M work days". Note - The verb "Cost" refers back to the plural subject "who" that modifies the plural noun "Americans".

We also see the correct Parallel structure. in medical expenses and lost work time . Here "in" is not repeated after "work time" and that is alright as ellipses is in play

C) year, so as to cost the nation $50 billion in medical expenses and lost - Incorrect.
So as to means so that. Thus we are now saying that they lose 64M work days so that they cost the nation $50B and this is completely illogical.

(D) year that costs the nation $50 billion in lost medical expenses and - Incorrect. the Nation loses $50B in "medical expenses" There is no such thing as "lost medical expenses". The only thing that is lost is the work days!

Note - I believe the usage of "that" is alright out here."That" can very well modify the preceding clause "who collectively lose 64 million workdays a year" thus stating that Americans lose 64M workdays a year and thus costs the nation $50B

(E) year, which thus cost the nation $50 billion in lost medical expenses and. Incorrect. Same error of (D) "lost medical expenses" + "which" may seem to refer to "year" and that would make the sentence illogical.


Correct Choice: (B)

HI GMATNinja, generis, AndrewN

In Option A, Pronoun ambiguity is not a hard rule eliminate so wanted to check, here Isn't they logically refers 64 million workdays ? How to eliminate A?

Hi Nandish

"They" in option (A) could logically refer either to "64 million workdays" or to "18 million Americans". Hence, there is an ambiguity about the antecedent of "they". This is clear error.

I would always be wary of eliminating an answer option solely based on pronoun ambiguity (unless I am able to find another answer option with no ambiguity and no other errors). In this case, however, we have another issue with option (A).

"and" following "year" shows the existence of a list that must obey parallelism. However, "who collectively lose..." and "they cost the nation..." are not parallel, with one being a relative pronoun and other a simple pronoun. If we begin the list after "who", then "collectively lose" is a verb form which is not parallel to "they cost the nation..." either. Basis the above, we can eliminate option (A).

Hope this helps.

Hello, NandishSS. I agree with what CrackVerbalGMAT has posted above. Speaking to your concern about pronoun ambiguity, no, it is not in itself a death sentence if an answer choice incorporates less-than-100-percent clear pronouns. Just do not lose sight of the five options presented. If a safer, harder-to-argue against alternative presents itself, as occurs in (B) above, then choose that option instead, every time. Watch the correct answers come rolling in. You may even think in terms of caution signs against different answer choices in the first pass, particularly if you cannot spot any clear violations. Take (A) and (B), for instance:



Now, between the two answer choices, you should ask yourself whether it is necessary to turn the sentence into a compound sentence. Is the comma warranted? Also, what about they? If it is not entirely clear, then you have two caution signs in that answer. In (B), though, the lack of a comma indicates two parallel elements, and lose and cost match up perfectly. Between the two answer choices, (B) is the clear winner.

I hope that helps. Thank you for thinking to ask me about this one.

- Andrew

AndrewN Is GMAT (thesedays) fine with the lack of comma in option B? I understand that this is a really old question so should I take it with a pinch of salt or be aware of this on the test day?

Good question, PyjamaScientist. Yes, the construct in (B) would be just as fine today without a comma before and thus. This exact structure can go either way in writing, but typically, if shorter elements are joined by the and, no comma is used.

He was tired and thus went to bed.

This iteration of the sentence better conveys a cause-and-effect relationship. He was tired and went to bed simply reports two actions. My guess is that GMAC™ decided that lose and cost were close enough in (B) not to warrant a comma, and since a comma plus and in a non-list sentence may suggest an independent clause, particularly in light of the original sentence, perhaps someone decided that the lack of a comma in (B) would present the safer, unambiguously correct option.

In general, I would not suggest using commas as a consideration for eliminating an answer choice. There are much better, more objectionable targets to pick off in just about any official SC question you could drum up.

Thank you for thinking to ask.

- Andrew

Hello PyjamaScientist,

We hope this finds you well.

To answer your query, Option B has no need for a comma, and indeed, should not have one, as it is simply listing two elements together - "lose 64 million workdays a year" and "cost the nation $50 billion in medical expenses"; Option B correctly links these two elements with conjunction (the phrase "and thus" in this case); remember, if a list contains only two elements, they must be joined by a conjunction.

We hope this helps.
All the best!
Experts' Global Team

GMATNinja, could you please clarify why cost and not costs is used in B?

Hello tkorzhan1995,

We hope this finds you well.

To answer your query, in this sentence the action of costing the nation $50 billion is done by the plural noun phrase "18 million Americans"; thus, the plural noun "cost" is correct.

We hope this helps.
All the best!
Experts' Global Team

Two inquiries on this question

(1) Could someone please explain further the parallelism issue with A (use of they).

(2) I went with Option A even though it did not seem perfect because in Option B, the meaning seems wrong. The meaning is conveying that "who collectively lose 64 million workdays per year" is leading to $50 billion in medical expenses and lost work time. Lost work time makes sense, but losing work days doesn't have an impact on medical expenses.

The problem with (A) is that it splits the sentence into two independent clauses:

• Migraine afflicts perhaps 18 million Americans, who collectively lose 64 million workdays a year
  
• [Those Americans] cost the nation $50 billion in medical expenses and lost work time

This splitting disconnects the missed workday part from the $50 billion part, making it sound a bit like this:

"Migraine afflicts perhaps 18 million Americans, who collectively lose 64 million workdays a year... and, incidentally, those Americans cost the nation $50 billion in medical expenses and lost work time."

It's unclear whether the $50 billion part has anything to do with the workdays missed because of migraines.

And the meaning in (B) is fine: in losing 64 million workdays a year, migraine sufferers cost the nation $50 billion in medical expenses. How exactly? The sentence doesn't say. But suggesting that these people rack up medical expenses when they have sick days seems reasonable enough.

I hope that helps!