This question is the second practice problem in the 4th series of Mean

The rise in American exports was possible because international trade barriers were lowered and unprecedented gains in efficiency had been obtained through the use of automated robotic equipment in American manufacturing plants.

A. international trade barriers were lowered and unprecedented gains in efficiency had been obtained through the use of automated robotic equipment in American manufacturing plants

HAD BEEN not necessary, stay in simple past "was possible" because x's were lowered, y were obtained (C)

B. America lowered international trade barriers and the use of automated robotic equipment in American manufacturing plants resulted in unprecedented gains in efficiency
meaning- not sure whether it was American lowering intl barriers or intl barriers globally, more importantly the use of x was not what made the rise possible, the gains in efficiency was one of the reasons

C. international trade barriers were lowered and unprecedented gains in efficiency were obtained through the use of automated robotic equipment in American manufacturing plants
Correct- meaning and verb tense

D. international trade barriers were lowered, obtaining unprecedented gains in efficiency through the automated use of robotic equipment in manufacturing plants of America
wrong modifier, not rise in exports

E. America lowered trade barriers internationally and the use of unprecedented automated robotic equipment in American manufacturing plants resulted in efficiency gains
meaning wrong with only America lowering and again robotic equip is not a reason

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Here is the official explanation for this question:

Understand the Meaning of the Original Sentence

This sentence presents a cause and effect. The effect is – rise in American exports. There are two causes:
• international trade barriers were lowered
• unprecedented gains in efficiency were obtained. This was done through the use of automated robotic equipment in US plants.

Find the Errors in the Original Sentence

1. The risein American exportswas possible
2. because
international trade barriers were lowered and
unprecedented gains in efficiency had been obtained through the use of automated robotic equipment in American manufacturing plants

All SV pairs are accounted for and agree in number. This sentence has verb tense error. Logically there is no reason to indicate one of the causes in simple past tense and the other cause in past perfect tense. There is no basis for such sequencing. Thus the verb – had been obtained – should be expressed as ‘were obtained’.

Review Answer Choices to do POE

Choice B – Grammatically Correct but Incorrect Choice – By changing the causes from passive voice to active voice, this choice adds information that is not present in the original choice. It is not stated that America lowered the international trade barriers. Thus, this choice is incorrect.

Choice C – Correct choice. The verb tense error has been corrected.

Choice D – This choice distorts the intended meaning. It links the two rather independent tasks in causal relationship. Per this choice, the international trade barriers were lowered and this led to achieving gains in efficiency through use of automatic equipment. This is neither logical nor the intended meaning.

Choice E – Grammatically Correct but Incorrect Choice – This choice repeats the error in Choice B. It further changes the intended meaning by using “unprecedented” to describe “automated robotic equipment” instead of “efficiency gains”.

TAKE AWAYS

1. Always understand the intended meaning of the original sentence.
2. It is very important to note ALL the information present in the sentence.
3. The correct choice should communicate ALL that information – no more and no less – in a grammatically correct manner.

I have a small doubt. Are the sentences B (America lowered international trade barriers and the use of automated robotic equipment in American manufacturing plants) and E(America lowered trade barriers internationally and the use of unprecedented automated robotic equipment in American manufacturing plants) grammatically parallel?

looking at the sentence in the below format, im little confused.

isnt it possible that (2) has happened in time before that of (1)? Such that 1 (happening at presnt) and 2 (happened before 1) is causing the rise in american exports?


The rise in American exports was possible because

1.international trade barriers were lowered
and
2.unprecedented gains in efficiency had been obtained

through the use of automated robotic equipment in American manufacturing plants


Thanks,
M

Hello ma'am,
If we do not specify who or how the international trade barriers were lowered, will it not be a case of dangling modifier?

Hello e-gmat and verbal experts

Can we use past perfect for the causes ?

international trade barriers had been lowered and unprecedented gains in efficiency had been obtained

correct answer is C because international trade barriers were lowered and unprecedented gains in efficiency were obtained written correctly.

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