Sentence Correction

bhumika.k.shah wrote:In a blow to those who still harbored the illusion that E-mail exchanges are private, a watchdog group recently uncovered a trick for enabling an interloper to rig an E-mail message so that this person will be privy to any comments that a recipient had added as the message is forwarded to others or sent back and forth.

(A) who still harbored the illusion that E-mail exchanges are private, a watchdog group recently uncovered a trick for enabling an interloper to rig an E-mail message so that this person will be privy to any comments that a recipient had added [HAD added implies event in the past - Eliminate]

(B) who had still been harboring the illusion that E-mail exchanges are private, a watchdog group recently uncovered a trick for enabling an interloper to rig an E-mail message so that this person was privy to any comments that a recipient might have added [WAS privy, again wrong tense - Eliminate]

(C) who still were harboring the illusion that E-mail exchanges are private, a watchdog group recently uncovered a trick enabling an interloper to rig an E-mail message so that this person is privy to any comments that a recipient would add
[Still were Harboring - Awkward - Eliminate]

(D) still harboring the illusion that E-mail exchanges are private, a watchdog group recently uncovered a trick that enables an interloper to rig an E-mail message so that this person will be privy to any comments that a recipient might add
[Correct]

(E) still harboring the illusion that E-mail exchanges had been private, a watchdog group recently uncovered a trick that will enable an interloper to rig an E-mail message so that this person was privy to any comments that a recipient might add
[WASP privy - Will add - Wrong tense - Eliminate]

Source GMAT Prep

What is the difficulty level and what are the reasons to eliminate all but the correct choice.

Thanks

bhumika.k.shah wrote:In a blow to those who still harbored the illusion that E-mail exchanges are private, a watchdog group recently uncovered a trick for enabling an interloper to rig an E-mail message so that this person will be privy to any comments that a recipient had added as the message is forwarded to others or sent back and forth.

(A) who still harbored the illusion that E-mail exchanges are private, a watchdog group recently uncovered a trick for enabling an interloper to rig an E-mail message so that this person will be privy to any comments that a recipient had added

(B) who had still been harboring the illusion that E-mail exchanges are private, a watchdog group recently uncovered a trick for enabling an interloper to rig an E-mail message so that this person was privy to any comments that a recipient might have added

(C) who still were harboring the illusion that E-mail exchanges are private, a watchdog group recently uncovered a trick enabling an interloper to rig an E-mail message so that this person is privy to any comments that a recipient would add

(D) still harboring the illusion that E-mail exchanges are private, a watchdog group recently uncovered a trick that enables an interloper to rig an E-mail message so that this person will be privy to any comments that a recipient might add

(E) still harboring the illusion that E-mail exchanges had been private, a watchdog group recently uncovered a trick that will enable an interloper to rig an E-mail message so that this person was privy to any comments that a recipient might add

Source GMAT Prep

What is the difficulty level and what are the reasons to eliminate all but the correct choice.

Thanks

bhumika.k.shah wrote:OA D

I wanted to know whats wrong in they way A,B and C begin?