Official Solution:


Goldman Sachs Inc. had been investing in Crystal Technologies, a cloud computing company, for several years, but they withdrew all their funding in 2008, and after a year Crystal went bankrupt.


A. had been investing in Crystal Technologies, a cloud computing company, for several years, but they withdrew all their funding in 2008, and after a year Crystal went bankrupt
B. has been investing in Crystal Technologies, a cloud computing company, for several years but withdrew all its funding in 2008, a year after Crystal went bankrupt.
C. had invested in Crystal Technologies, a cloud computing company, for several years, but it withdrew all its funding in 2008; a year after it went bankrupt.
D. had been investing in Crystal Technologies, a cloud computing company, for several years but withdrew all its funding in 2008, a year after which Crystal went bankrupt.
E. was investing in Crystal Technologies, a cloud computing company, for several years, but a year before it went bankrupt in 2008, it withdrew all its funding.


A. The pronoun “they” and “their” do not have a proper antecedent - the company Goldman Sachs Inc. is singular.

B. Present perfect continuous “has been investing” is wrong. Present perfect implies that the action is still continuing to happen till the present moment, whereas the action actually ceased to continue in 2008. Here it is required to depict an action that was continuing to happen in the past and hence a past continuous or a past perfect continuous is required. A past perfect continuous is more appropriate than a past continuous here, because there exists a time reference (2008) in the sentence till when the action investing continued to happen - without this time reference, past continuous would be alright.

The part “a year after Crystal went bankrupt” is a run-on sentence. Since this part is an independent clause, it must be separated by either a semicolon or a conjunction.

C. The past participle tense “had invested” is wrong. The action investing continued for several years in the past and hence either a past continuous or a past perfect continuous must be used. A past perfect continuous is more appropriate than a past continuous here, because there exists a time reference (2008) in the sentence till when the action investing continued to happen - without this time reference, past continuous would be alright.

The pronoun “it” occurs twice in the sentence - once it refers to “Goldman sachs Inc.”, the other time it refers to “Crystal Technologies”. It is not allowed in GMAT to use the same pronoun to refer to two different antecedents in the same sentence.

D. CORRECT. Past perfect continuous “had been investing” is used to depict an action that continued to happen in the past for a certain period of time till a time reference (2008).

E. Use of past continuous “was investing” is questionable. A past perfect continuous is more appropriate than a past continuous here, because there exists a time reference (2008) in the sentence till when the action investing continued to happen - without this time reference, past continuous would be alright.

The pronoun “it” refers to Goldman Sachs Inc. (If there are two possible antecedents for a pronoun that is the subject of a clause, by virtue of parallelism, this pronoun refers unambiguously to the subject of the other parallel clause.) Thus this construction changes the meaning - it implies wrongly that Goldman Sachs went bankrupt.


Answer: D
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The question or/and solution has been revised and edited. Thank you sayantanc2k !!!
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