Subject phrases and Clauses: always singular?

Answer is E. "when unaccpmpanied correspondigly" sounds awkward and wordy. We want something along the lines of "when unaccompanied by ocrredsponding increases in sales..."

a)awkward and wordy
b) "possibly leads" is also awkward.
c) even MORE awkward and wordy than the original... unnecessary pronoun in addition.
d) "possibly leads" is awkward.
e) CORRECT! This gets rid of the wordiness of the original and adds no new errors.

I chose answer E. Concise and grammatically correct

IMO: E

Rising inventories, when unaccompanied correspondingly by increases in sales, can lead to production cutbacks that would hamper economic growth.

A - when unaccompanied correspondingly by increases in sales, can lead
B - when not accompanied by corresponding increases in sales, possibly leads
C - when they were unaccompanied by corresponding by sales increases, can lead
D - if not accompanied by correspondingly increased sales, possibly leads
E - if not accompanied by corresponding increases in sales, can lead

Answer: E
Explanation:
splits: when and if & can lead and possibly leads.
I think this is hypothetical situation, so answer should be either D or E.
From D and E, E is better choice bcz the verb 'leads' does not match with plural noun 'inventories'

option e

My answer - E

I believed the best choice is letter "E"

Phrase or clause is the subject of a sentence and is always considered as one hence, singular....

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