Parallelism | OG | Ryunosuke Akutagawa‘s knowledge

Hi Experts,

Can you please highlight why D is incorrect? I do not want to eliminate this due to pronoun ambiguity.

let us look at each of the answer options -

A - 'that of' is unnecessary and breaks the parallelism. 'Europe, China and Japan'is the correct usage. Also, the word 'knowledge' is singular.

B - usage of 'that of' is incorrect.

C - correct answer. Note that 'informing ...' is a comma + -ing form at the end of a clause.
This applies to the subject - 'Akutagawa's knowledge' and serves as a subordinate action/description of the main clause.
It answers the question "how was his knowledge instrumental in his development?"

D - the usage of 'as much as' is ambiguous. Note that 'as much as' requires parallelism.

look at his example -
she loves computer games as much as her husband. this sentence can be interpreted in two ways -

she loves [computer games] as much as [her husband] - here 'her husband' is parallel to 'computer games'.
this implies that 'she loves computer games as much as she loves her husband'

OR
[she] loves computer games as much as [her husband] - here 'her husband' is parallel to 'she'
this implies that 'she loves computer games as much as her husband loves computer games'.

So, this sentence can mean - knowledge informed his literary style as much as the content of his fiction informed his literary style OR
knowledge informed his literary style as much as knowledge informed the content of his fiction.

E - knowledge is singular. Hence 'were' is incorrect. Also, note that 'both' + 'in addition to' is incorrect. 'both' requires an 'and'.