Directions: The following question presents a sentence, part of which or all of which is underlined. Beneath the sentence you will find five ways of phrasing the underlined part. The first of these repeats the original; the other four are different. If you think the original is best, choose the first answer; otherwise choose one of the others.

A recording system was so secretly installed and operated in the Kennedy Oval Office that even Theodore C. Sorensen, the White House counsel, did not know it existed.

A is correct because it properly uses the 'so X that Y' construction to show the extent of the secrecy: 'so secretly installed and operated...that even [someone] did not know.' B is incorrect because 'so secret was...' puts 'secret' before the noun, which changes the meaning from adverb to adjective. C is incorrect because 'it was so secret that...' is wordy and changes the emphasis. D is incorrect because 'that was so secretly...' is wordy and doesn't properly complete the thought with 'that.' E is incorrect because it creates an awkward inverted structure that doesn't flow naturally.