C is not in the passive voice. The verbal form does not change. In the original we have 'led to passing' and in C we have 'led to the passage'. The relevant correction is from the verbal form "passing" to the noun form "passage".

The GMAT always prefers a sentence that uses an original noun, such as 'passage', instead of a verbal form derived from the same root 'passing' < 'to pass'.

So, when you see alternating forms such as 'passage' vs. 'passing' / 'arrival' vs. 'coming' / 'departure' vs. 'departing'/ etc. - always choose the bona fide noun over the derivative form.

in A led to passing the is wrong........

A - "allowing companies to seek upto......" is a participle modifier that modifies the passing of ACC protection act. So this is wrong.

B and C - eliminates the modifier problem by using "which" by modifing only the ACC protection act.
B - that they will sell ( redundant, and ambigious "they"),
that they will sell ( also changes the meaning of the original sentence )
C - perfect ( eliminates modifier problem and removes the pronoun ambiguity )


Please dont eliminate answer choice by active and passive voice. Some times passive voice is preferred. Please read this ron's post.
https://www.beatthegmat.com/companies-in ... tml#367644

Moreover here C is not passive as explained above.

Since you have alrady identified the problem in D and E, I am not discussing that.

Hope this explanation helps.