1. Identification of Error: Parallelism error in 'Not only... but also' construction. The elements linked by the correlative conjunctions are not grammatically parallel.
2. Grammatical Rule: In "Not only... but also" constructions, the elements linked must be grammatically equivalent. If a verb phrase or a clause with an active verb follows "Not only", a grammatically similar verb phrase or clause should follow "but also", ideally maintaining the original intended meaning.
3. Option Elimination:
A. Incorrect — The phrase "does the committee scrutinize" (an active verb phrase) is not parallel with "its intention is to ensure" (a noun phrase followed by a linking verb and an infinitive phrase), violating the rule of parallelism.
B. Correct — "it intends to ensure" is an active verb phrase that is parallel in structure to "does the committee scrutinize." This option also accurately preserves the original meaning of 'intention' or 'purpose'.
C. Incorrect — This option uses a gerund phrase as the subject ("ensuring... is also its intention"), which is not parallel to the active verb phrase in the first part of the sentence.
D. Incorrect — While "it also ensures" creates parallelism with "does the committee scrutinize," it subtly alters the meaning from an 'intention to ensure' to an 'actual ensuring' or 'outcome', thus not optimally preserving the original nuance conveyed by "its intention is to ensure".