boomgoesthegmat wrote:Ryonosuke Akutagawa's knowledge of the literatures of Europe, China, and that of Japan were instrumental in his development as a writer, informing his literary style as much as the content of his fiction.

A) that of Japan were instrumental in his development as a writer, informing his literary style as much as

The given sentence seeks to establish a sequence describing Akutagawa's knowledge of the literatures of Europe, China, and Japan. There is no reason to insert THAT OF before JAPAN, and since THAT OF is singular, it refers to KNOWLEDGE, thus causing the sentence to refer to Akutagawa's knowledge of the knowledge of Japan, which is clearly nonsensical. Since THAT OF is superfluous, you can eliminate options A and B.

B) that of Japan was instrumental in his development as a writer, and it informed both his literary style as well as

After eliminating the first two options, you should notice that options C and D use WAS and that D uses WERE. Since the subject of these verbs is KNOWLEDGE, you can eliminate option E. Your real work starts now: you have to see what is wrong with one of the other two options and why the other is right.

C) Japan was instrumental in his development as a writer, informing both his literary style and

This option has no grammatical errors or conceptual problems of any kind. Note the parallel structure after the correlative conjunctions BOTH something AND something. Furthermore, the phrase informing both his literary style and the content of his fiction works perfectly to explain - as such phrases characteristically do - the previous information. The idea created is that Akutagawa's knowledge helped his development as a writer since it informed two essential aspects of his work.

D) Japan was instrumental in his development as a writer, as it informed his literary style as much as

This option is incorrect for the following reasons. First, the use of AS here as a synonym for BECAUSE is not favored in the GMAT, for reasons that are not clear to me, but the fact is that when AS performs this function, there is something wrong somewhere in the option.
Second - and this is more important - the statement that the knowledge informed his literary style as much as the content of his fiction is nonsensical. AS MUCH AS indicates that something is quantifiable and measurable: a kilo of feathers weighs as much as a kilo of butter, and if there are two equal-sized heaps of flour on a table, there is as much flour in one heap as in the other. But how can one quantify how much knowledge has gone into the style and how much into the content of this writer's fiction? AS MUCH AS implies here that what cannot be measured is in fact measurable.
Third, this same statement seems to want to want to make an elliptical comparison and say that the knowledge informed the literary style as much as the content of the fiction informed the literary style - an idea that is, at best, unclear.


E) Japan were instrumental in his development as a writer, informing both his literary style in addition to

C