DARPA’s Falcon Hypersonic Technology Vehicle can fly as fast as 6X the speed of sound and can attack a target 2000 miles away in 30 minutes, its engine’s thrust prevented from dissipating in the stratosphere by its conical unibody design.
A. its engine’s thrust prevented from dissipating in the stratosphere by its conical unibody design
B. preventing its engine’s thrust from dissipating in the stratosphere because of its conical unibody design
C. preventing the dissipation of its engine’s thrust in the stratosphere due to its conical unibody design
D. prevented its engine’s thrust from being dissipated in the stratosphere by its conical unibody design
E. its engine’s thrust is prevented from being dissipated in the stratosphere because of its conical unibody design
Here is the official explanation for this question:
Understand the Meaning of the Original Sentence
The sentence presents a fact about DARPA’s Falcon Hypersonic Technology Vehicle (FHTV). It states that this vehicle can fly as fast as 6 times the speed of sound. It can attack a target 2000 miles away in 30 minutes. Then the sentence presents the reason why such performance is achievable. The engine’s thrust is prevented from being dissipated in the stratosphere. This is because of the conical unibody design.
Find the Errors in the Original Sentence
• DARPA’s Falcon Hypersonic Technology Vehicle can fly
as fast as 6X the speed of sound and can attack
a target 2000 miles away in 30 minutes, its engine’s thrust prevented from dissipating in the stratosphere by its conical unibody design.
This sentence contains a single clause with the SV pair highlighted. The underlined portion of the sentence contains a modifier – a noun + noun modifier structure. This modifier provides further information about how the vehicle can fly this fast and can attack this fast and this far away. The sentence has no grammatical errors and communicates the meaning very clearly.
Review Answer Choices to do POE
Choice B – Even though grammatically correct, this choice distorts the meaning of the sentence since now it uses “verb-ing modifier” in place of “noun + noun modifier”. Thus instead of now presenting a mechanism of how the vehicle is this fast, it presents the following two meanings, both of which are illogical:
1.The vehicle itself prevents its thrust from dissipating – Illogical.
2.The vehicle goes this fast and this results in preventing its thrust from dissipating. – Reversed causal relationship - hence illogical.
Choice C – Same errors as in Choice B. Furthermore, “due to” is not used correctly. Here it may illogically imply that the dissipation of thrust is due to conical design.
Choice D – Use of verb-ed modifier in this sentence is not correct. Typically these modifiers are used to modify the nouns. Even if they are used to modify the clauses, they associate with the subject of the clause, and this is non-sensical in the context of this sentence as discussed in choice B analysis.
Choice E – This choice connects two independent clauses using comma. Semicolon should be used. Furthermore, this choice is very wordy.
1. Understand the meaning of the original sentence and determine the role of each modifier.
2. Be cautious of change of structure of modifiers since such changes even though grammatically correct may distort the meaning of the sentence.
Note: The attachment at http://gmatclub.com/forum/5-strategies-that-gmat-uses-to-distort-meaning-124296.html
contains the document with Strategies for Meaning Change and the questions with detailed solutions. Note that this is a "living" document. We add the strategies, questions, and explanations in this document as we add them on the forum. So be sure to download the latest version!
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