Scientists say that by bathing the skin cells in extracts of immune c

Hello Everyone!

Let's tackle this question, one thing at a time, and narrow down our options quickly so we know how to answer questions like this when they pop up on the GMAT! To begin, let's take a quick look at the question and highlight any major differences between the options in orange:

Scientists say that, by bathing the skin cells in extracts of immune cells, that human skin cells in a test tube are made to behave as if they were immune system cells.

A) that human skin cells in a test tube are made to behave as if they were

B) that human skin cells were to behave in a test tube as if they were

C) human skin cells in a test tube were made to behave as if

D) they have made human skin cells in a test tube that were behaving as

E) they have made human skin cells in a test tube behave as if they were

After a quick glance over the options, there are a few key differences we can focus on:

1. that human skin cells / human skin cells / they have made human skin cells (Construction)
2. are made to behave / were to behave / were made to behave / that were behaving / behave (Verb Tense & Active/Passive Voice)
3. as if they were / as if / as (Idioms)

Let’s start with #1 on our list, which has to do with construction. If we look at the original sentence, we see that there is a non-essential phrase we can remove:

Scientists say that, by bathing the skin cells in extracts of immune cells, that human skin cells in a test tube are made to behave as if they were immune system cells.

If we remove this non-essential phrase, what we have left over still needs to make sense. Let’s do a quick check to see if our options are constructed properly. To make this easier to spot, we’re going to add in “Scientists say that” to each option:

A) Scientists say that that human skin cells in a test tube are made to behave as if they were

B) Scientists say that that human skin cells were to behave in a test tube as if they were

C) Scientists say that human skin cells in a test tube were made to behave as if

D) Scientists say that they have made human skin cells in a test tube that were behaving as

E) Scientists say that they have made human skin cells in a test tube behave as if they were

We can eliminate options A & B because they repeat “that” twice, which isn’t necessary or grammatically correct to do here. Now that we have it narrowed down, let’s tackle #2 on our list: Verb Tense & Active/Passive Voice. We need to make sure any option we choose is in active voice, and we also need to make sure the verb tenses make sense for the intended meaning:

C) human skin cells in a test tube were made to behave as if → Passive Voice = WRONG

D) they have made human skin cells in a test tube that were behaving as = OKAY

E) they have made human skin cells in a test tube behave as if they were = OKAY

We can eliminate option C because it uses passive voice, which is a big no-no on the GMAT! Now that we have it narrowed down to only 2 options, let’s tackle #3 on our list: Idioms. The phrases “behave as X” and “behave as if they were X” are slightly different things:

D) they have made human skin cells in a test tube that were behaving as immune system cells.
This is INCORRECT because saying “X behaving as Y” changes the intended meaning. The sentence we have here suggests that the scientists created the human skin cells, which isn’t accurate. The cells already existed - they just put them in a test tube and made them do something. This sentence is also saying that the human skin cells that scientists created were already acting like immune system cells - not that the doctors did anything to make them behave that way!

E) they have made human skin cells in a test tube behave as if they were immune system cells.
This is CORRECT! This clearly shows that the human skin cells already existed, and that the scientists were able to make them do something - behave as if they were a different kind of cell.

There you have it - option E is our winner! It uses clear verbs, wording, and idioms to properly convey the intended meaning!

Don’t study for the GMAT. Train for it.

Scientists say that, by bathing the skin cells in extracts of immune cells, that human skin cells in a test tube are made to behave as if they were immune system cells.

A) that human skin cells in a test tube are made to behave as if they were

B) that human skin cells were to behave in a test tube as if they were

C) human skin cells in a test tube were made to behave as if

D) they have made human skin cells in a test tube that were behaving as

E) they have made human skin cells in a test tube behave as if they were

A. two back to back "that' make the sentence incomprehensible.
B. Same as A
C. By bathing the cells what have they done? The next part of the sentence should say what have the scientists done
D. Were behaving as is wrong tense
E. Correct

Hi generis could you please explain how can E be the answer for this Question.

Answer choice E contains Pronoun "they" and They refers to Scientist I guess In first place and second they refers to human skin cells. Logically a pronoun cannot refer to multiple antecedents.

Scientists say that, by bathing the skin cells in extracts of immune cells, that human skin cells in a test tube are made to behave as if they were immune system cells.

A) that human skin cells in a test tube are made to behave as if they were

B) that human skin cells were to behave in a test tube as if they were

C) human skin cells in a test tube were made to behave as if

D) they have made human skin cells in a test tube that were behaving as

E) they have made human skin cells in a test tube behave as if they were

Meaning:
Scientists say that...that humans skin cells in a test tube are made to behave as if they were.
You'll notice I crossed out the second that, as the sentence can't make sense with both of them.
Meaning-wise it makes sense to say, "Scientists say [in the present] that [in the past] they made human skin cells behave [general statement].

Grammar:
We should generally avoid passive voice "are made to behave". It'd be better if it were active.

A and B have double that.

C loses the meaning at the end. It should be "as if they were immune cells". "As if immune cells" doesn't make sense.

D loses the meaning by removing "as if", and it doesn't make sense to transform the phrase "they have made human skin cells behave", into a necessary modifier "they have made human skin cells that were behaving". That's not what the scientists did: they made skin cells behave in a certain way.

E is the only one that's correct.

Important note about pronouns for vishumangal: pronouns generally refer to the closest appropriate subject before them. So, using they to refer to scientists and then to skin cells is fine, in the same way I could say "My brother said that he told my friend that he was behaving badly." The first he clearly refers to my brother, the second he clearly refers to my friend (the subject right before it).

Hi GMATNinja,

Can you please throw some light on this question. Just want to understand usage of 2 that's and 'if'.

Thanks for your help.

Vaibhav

Clearly, A and B are out for repeating 'that' which is illogical in the context that 'Scientist say that(removing the part within comma 'by ... cells') something ....'.
C loses out for not being a complete sentence.
In D the behaving requires 'as if ... clause'. Though clause is there, it misses out on meaning part. As per meaning Scientists made human skin cells behave in a certain manner whereas D says Scientists made human skin cells that were by themselves behaving in that manner. It suggests Scientists didn't made the human skin cells behave instead that behaviour came naturally to these cells.
E is correct but the two 'they' used create, at first sight an ambiguity which it is not.

Please look at
https://gmatclub.com/forum/michelangelo ... s#p2509603
This one has pronoun as one of the deciding factor though.

E is the answer.

GMATNinja VeritasKarishma

Can you please let me know how E is a right answer, even-though this answer choice is changing the intended meaning.

Answer choice E says Scientists themselves have made skin cells behave like immune cells, but original sentence does not say the same.

Remember, as explained in this post, there is nothing special about the meaning in choice (A), and (A) does not give us the "intended" meaning! You have to FIND the sentence where the meaning makes the most sense, regardless of how that sentence compares to choice (A).

So if you think (E) makes more sense than the others, you've found the winner.

I hope this helps!

Hi GMATNinja

Whether it is correct that the a common pronoun (in the given question 'they') have dual antecedents as in option E ?

Well, (E) is the correct answer here, so, according to GMAT, yes!

As discussed in this video, a little pronoun ambiguity doesn't necessarily make a sentence wrong on the GMAT. In this particular case, it's fairly obvious that the first "they" must refer to the scientists. Who made the skin cells do something in a test tube? A bunch of cells wearing lab coats and safety goggles? No, it was the scientists.

And were the "human skin cells in a test tube" made to behave as if the SCIENTISTS were immune system cells? Of course not. The "human skin cells in a test tube" were made to behave as if they were immune system cells.

The intended meaning is totally clear, so in this case having two instances of "they" with different antecedents isn't a major issue.

I hope that helps!

Hi GMATNinja,
Can you please clarify uses of two verbs in a single clause in Option E that they have made human skin cells in a test tube behave ......

It might help to consider a simple example:

Tim made his children dance for their supper, tossing fish heads in their general direction as the little scamps popped and locked as though their lives depended on it.

It feels as though you've got two subject-verb pairings within the same clause. One action, "made," is performed by Tim, while the other action, "dance" is performed by the kids. There's nothing inherently wrong with this -- you probably didn't have any difficulty understanding what the sentence conveys.

If I write the sentence like this, "Tim is forcing his children to dance," I'm communicating the exact same information, but now it seems as though "to dance" functions as a modifier, describing what Tim forced his kids to do. So it doesn't really matter whether you want to think of "dance" as an action performed by the kids or as a modifier providing context for what Tim forced his children to do. The important thing is that it makes sense, and it shouldn't have jumped out as concrete error.

Same deal in (E):

You can see "behave" as a modifier for what they forced the skin cells to do, or you can see it as an action performed by the skin cells. Either way, it seems fine.

Put another way, if you ever encounter a construction that seems questionable, and your first thought is, "can we do that?" but the sentence is logical, try not to use that construction as a decision point. There are simply too many valid ways to assemble a given sentence to absorb all of them.

I hope that helps!

GMATNinja
Dear Charles,
could you elaborate why B is wrong?

Pursuant to your explanation, "that" can stand for article, signifying "that human skin cells" tantamount to "the human skin cells"

B) Scientists say that that human skin cells were to behave in a test tube as if they were

Thank you in advance.

Hey AndrewN , does option D also give an impression that somehow the test tube was performing the action of behaving by adding the word that after test tube. I get that there are other obvious reasons and that test tube is singular here.

Yes, Brian123, it can be jarring to read test tube that, which sets us up to believe that information about the test tube will follow, and then encounter were, a verb that requires us to jump back over the test tube to a plural noun instead. A careful reading of (D) should allow us to see past an interpretation that the test tube itself was behaving a certain way, but that does not mean that the sentence is clear or written well. If the doubts start to stack up on any given answer, you should probably go with a safer bet.

Thank you for thinking to ask me.

- Andrew

I read the answer in OG2020. In choice C. human skin cells in a test tube were made to behave as if.
OG told that human skin cells in a test tube were made is unnecessary and awkward. Why is passive voice here awkward

Hi Tanchat, there is obviously a modifier issue in C: by bathing the skin cells in extracts of immune cells should have modified Scientists, but it's actually nonsensically modifying human skin cells.

Also, the passive voice human skin cells in a test tube were made to behave does not tell us who made human skin cells behave this way. E uses active voice to clearly indicate that scientists made human skin cells behave this way.