The chief problem in this topic is to succumb to the tempting assumption that scientists removed the natural hormone, before they could synthesize it. However, the text does not specify this. After all the text itself is a fragment with only an introductory subordinate clause but without a main clause

This is the reason that choices B, D and E fall flat, which categorically state that the scientists removed the hormone. In addition, in D, since the pronoun ‘it’ refers to ‘the synthetic growth hormone’ you have the logical question of how anyone could have removed a synthetic hormone, even before knowing how to make it or synthesize it.

C avoids the first pitfall by tactfully switching over to a passive voice, leaving the question of who removed the hormone wide open. In addition and aptly, the pronoun ‘it’ in C simply refers to a growth hormone and not a synthetic growth hormone.
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A) scientists learned how to make a synthetic growth hormone, removing it painstakingly - Wrong way to phrase the sentence.
B) scientists had learned about making a synthetic growth hormone, they had to remove it painstakingly - Use of "had" 2 times is wrong.
C) scientists learned how to synthesize the growth hormone, it had to be painstakingly removed - part marked in RED changes the meaning of the sentence. Scientists did not learn to synthesize the hramone itself, they just learned how to make the synthetic harmone.
D) learning how to make a synthetic growth hormone, scientists had to remove it painstakingly - correct and only remaining answer.
E) learning how to synthesize the growth hormone, it had to be painstakingly removed by scientists - Same as C.

OA is C

as everybody has said, C and D are really close. That's why the question,IMO, is hard.

D) Before learning how to make a synthetic growth hormone, scientists had to remove it painstakingly in small amounts from the pituitary glands of human cadavers.

The main problem with D is that "it" refers to "synthetic growth hormone" and not only to synthetic growth hormone. Pronouns refer to the adjectives-noun. In addition, the scientist did not remove the growth hormone, so option C correctly uses the passive voice.

This is really a typical sc which test profound meaning. C and D are both correct in grammar but have different meanings.
D is illogical jerk because it means that: before scientists learn how to synthesize a hormone, they had to remove it (hormone) from nature (which is one of a step in the hormone synthetic process) --> so if hormone is already there, scientists dont have to synthesize it.
C is rational because it means: before scientists learn to synthesize a hormone, hormone had to be removed from nature (because people have not synthesise it yet so they have to use hormone from nature resource). --> that's the meaning of C.
this idea has come up with me when i've browsed this link, found it is very useful to read Ron's explanation.
http://www.manhattangmat.com/forums/bef ... -t637.html

Agree with C.

You have to also look at "make a synthetic growth hormone" vs "synthesize the growth hormone " . You cannot make a synthetic hormone; you can only synthesize it.

Hope this helps.

Crick

Isnt C a "Run ON"?

scientist learned how to synthesize the growth hormone - an independent statement
it had to be painstakingly removed - another independent statement

both statements are not connected with conjunctions or coordinating conjunctions etc... PLease help.

Before scientists learned how to make a synthetic growth hormone, removing it painstakingly in small amounts from the pituitary glands of human cadavers.
The sentence is meant to say - before scientists learnt how to make synthetic growth hormones , they used to go through the painful way to extract the hormones ( growth hormones) i.e the growth hormones were removed from human cadavers

A. scientists learned how to make a synthetic growth hormone, removing it painstakingly
Sentence fragment . There is no working verb in the sentence - "before scientists learned <> , removing it <>"
the "IT" here refers to "synthetic growth hormone" , rather than "growth hormones" ( it was not the "synthetic growth hormones" that they removed from human cadavers , but was the growth hormones .

B. scientists had learned about making a synthetic growth hormone, they had to remove it painstakingly

*error in tense. The learning of making synthetic hormone , happened after they used to remove growth hormone in a painstaking way . Hence "had" in first part of sentence is incorrect.
* the "IT" in second part of the sentence refers to "synthetic growth hormone " rather than just "growth hormone" , conveying an absurd meaning that "before scientists learned to make synthetic growth hormone , they used to remove synthetic growth hormone from pituitary glands".

C. scientists learned how to synthesize the growth hormone, it had to be painstakingly removed
CORRECT : the "IT" here refers to "growth hormone" , hence conveying a correct meaning.Sentence is framed in a proper Tense.

D. learning how to make a synthetic growth hormone, scientists had to remove it painstakingly
Same issue with "IT" as in A and B.

E. learning how to synthesize the growth hormone, it have to be painstakingly removed by scientists

*Modifier error- doesn't convey who is synthesizing the growth hormone ( comma should immediately follow with the noun scientist . Which is not the case here).
Tense error - messes up the tense issue ( should be "had" instead of "have" , since this action is not happening anymore now and this happened before the scientists learned to synthesize).

-Jyothi
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Before scientists learned how to make a synthetic growth hormone, removing it painstakingly in small amounts
from the pituitary glands of human cadavers.

1:meaning analysis
before scientists learned how to make a synthetic growth hormone, they had to remove the growth hormone painstakingly in small amounts from its place.

2:error analysis
sentence fragment. dependent clause+,+ phrase

3:POE
A.
B. scientists had learned about making a synthetic growth hormone, they had to remove it painstakingly
in fact the second sentence's verb must be stated in past participle from + it in the second part refers to a synthetic growth hormone while it should refer to growth hormone

C. scientists learned how to synthesize the growth hormone, it had to be painstakingly removed

D. learning how to make a synthetic growth hormone, scientists had to remove it painstakingly
changes meaning. it implies that before learning how to do x they had to do y+ pronoun reference error "it" refers to a synthetic growth hormone while it should refer to growth hormone

E. learning how to synthesize the growth hormone, it had to be painstakingly removed by scientists
modifier error+ no need for the passive form

addict1ve thanks for your Kudos,

we use past perfect form when verb sequencing is present. it means two actions took place in the past, and one of these actions happened earlier than the second one+ these two actions are related.

for example: his wife divorced him because he had had an affair. "had had affair" is the earlier action and "divorced" is the later action.

here by "in fact the second sentence's verb must be stated in past participle form" I meant if we want to use past participle verb form, we should use it for the earlier action. the earlier action here is removing the growth hormone painstakingly, and the action of learning is the later action.
so for sure the usage of past participle form of the verb for earlier action in choice B is incorrect.

however, by your question I've remembered three important points:
1- we use past perfect from for two actions that are related.
2- both actions should be in the past tense
3- if time marker is present in the sentence, using past perfect is not necessary. ( under this condition if the earlier action expressed in simple past then the sentence is not incorrect)

hope it helps.

In A, as you said, it can refer back to "synthetic growth hormone" but it is a pronoun and so it can refer back only to noun, which is growth hormone in this case. Over here "synthetic" is working like an adjective so "it" should not refer back to "synthetic growth hormone". Just my understanding, I might be wrong.

Experts can you please guide.



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