GMAT Instructor
Joined: 01 Jul 2017
Posts: 89
Given Kudos: 11
Location: United States
Concentration: Leadership, Organizational Behavior
Re: Since they knew that seniors are apt to injury, the architect of the
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06 Jan 2018, 14:00
As we look at the structure of this question, we can see that the sentence we are worried about begins with either a dependent clause or a modifying phrase. Since each of these grammatical constructions follows very different rules, let’s evaluate each answer choice one at a time.
Answer choice A begins with a dependent clause (triggered by the word “since”.) Dependent clauses are not modifiers, so they do not need to obey the “as-close-as-grammatically-possible” rule that modifiers normally follow. However, answer choice A contains the pronoun, “they”, which has no clear antecedent. “They” is plural, and the plural options in the sentence are “seniors”, “staircases”, and “railings” – none of which makes sense in this context. It is the architect who knows that seniors are apt to injury. Architect is singular, allowing us to eliminate A because of a pronoun error.
Answer choice B begins with the phrase “having known”. This is an adjectival modifier called a perfect participle. Perfect participles are grammatically legal, but they are often used by the GMAT as Style errors because of their unnecessarily awkward construction. However, the larger problem with answer choice B is the meaning it conveys. A perfect participle communicates a similar idea as the past perfect verb tense does: two events took place in the past, and one of the events finished first. When answer choice B says “having known that seniors are apt to injury, the architect…designed…”, this means that the architect first knew the seniors are apt to injury, but then he stopped knowing that fact prior to designing the retirement home. This makes no sense, and makes it easy to eliminate answer choice B.
The phrase in answer choice C, “Seniors being apt to injury” is an appositive – a substitutive noun phrase that modifies another noun. However, the word “seniors” cannot substitute for “architect”, so we can certainly eliminate answer choice C. (Note that the word “being” is not a verb in this context – it is a present participle that modifies “seniors.”) Some test-takers feel that answers containing the word “being” can be eliminated out of hand, but this is a false heuristic. In this context, “being” is completely legal grammatically. It just doesn’t make sense.
Answer choice D contains no pronoun or meaning errors. Some test-takers mistakenly eliminate answer choice D because it seems to contain a construction similar to answer choice B (since both answers begin with words ending in -ing.) However, D is completely different. Answer choice B uses the phrase “having known” – a participle phrase that communicates a past-tense completion of a process. Answer choice D begins with the phrase “knowing” – a participle that communicates an ongoing present-tense process. Thus, when D uses the phrase, “knowing that seniors are apt to injury” to modify the word, “architect”, it describes how the architect used his knowledge of the injury rate of seniors to design the retirement home. D is the correct answer.
Answer choice E begins with a dependent clause (triggered by the word “since”.) Dependent clauses are not modifiers, so they do not need to obey the “as-close-as-grammatically-possible” rule that modifiers normally follow. However, answer choice E contains an error in meaning. The word “more” – not found in any other answer choice – is a great leverage word. E describes how seniors are “more apt to injury”, thereby setting up a comparison without actually comparing seniors’ rate of injury to any other rate. It almost sounds like the sentence is saying seniors are more apt to injury than the architect is. While this might be true, it makes no sense to communicate it in this way. E can be eliminated.