大全222的问题

By a vote of 9 to 0, the Supreme Court awarded the Central Intelligence Agency broad discretionary powers enabling it to withhold from the public the identities of its sources of intelligence information.

(A) enabling it to with hold from the public

(B) for it to with hold from the public

(C) for with holding disclosure to the public of

(D) that enable them to with hold from public disclosure

(E) that they can with hold public disclosure of

Choice A is best: enabling ... clearly modifies powers, it refers logically and grammatically to the Central Intelligence Agency, and to withhold from the public is concisely and idiomatically phrased. In choices B and C, the preposition for is used unidiomatically in place of the "-ing" modifier to introduce the phrase describing powers. In choices C, D, and E, with holding ... disclosure is wordy and imprecise, since it is really the identities that are to be withheld. The plural pronouns them in D and they in E do not agree with the singular Agency, and that in E mistakenly introduces a new independent clause rather than a modifying phrase for powers.
请问 the identities of its sources of intelligence information.在这句中的作用？