I find this question similar to some OG question , although i dnt remember that question . Anyways IMO D.

I have a difficulty in understanding this "The orignal sentence is incorrect because the conjunction when introduces an adverbial modifier, and an adverb cannot modify the noun condition. "

prachich1987 wrote:I have a difficulty in understanding this "The orignal sentence is incorrect because the conjunction when introduces an adverbial modifier, and an adverb cannot modify the noun condition. "

Generally speaking, "when" is not properly a relative pronoun like "which," but is in fact a relative adverb. Thus its correct usage is, for example:

"I am going to retire when this semester is over." Here, "when this semester is over" is an adverbial phrase modifying the verb "retire."

However, "when" CAN be an adjectival modifier if and only if it's modifying a time:

"Tomorrow is the day when you will meet your fate." Here, "when" is introducing a relative clause modifying the noun "fate." However, this is the only correct idiomatic usage of "when" as a relative (adjectival) pronoun.

In the above sentence, although it's not given as an option, we could replace "when" with "in which" and no longer have an error. Then, "which" would be referring to "condition" and the relative clause "in which your eyes bridge the gaps..." would properly modify the noun "condition."

6. Persistence of vision, the condition when your eyes bridge the gaps of darkness between flashes of light, explains the seeming magic produced by the stroboscope, an instrument that appears to freeze the swiftest motions while they are still going on.

A) the condition when your eyes bridge - incorrect use of appositive
B) when your eyes bridge - incorrect use of when to modify vision
C) the condition of your eyes bridging - bridging is incorrect
D) which occurs when your eyes bridge - Correct
E) occuring when your eyes bridge - ing modify preceding clause

IMO - D

Hi Adam

I am pretty lost in this problem, You said that when can be replaced by in which . Hence D is correct but in option D there is no in which . Option D has only which .

As far as I know, which refers to the nearest noun, that is in this case is vision and not persistence of vision.

Please explain.

A good one.