aback

IPA: ʌbˈæk

(archaic) Towards the back or rear; backwards.
(archaic) In the rear; a distance behind.
By surprise; startled; dumbfounded. (see usage)
(nautical) Backward against the mast; said of the sails when pressed by the wind from the "wrong" (forward) side, or of a ship when its sails are set that way.

Examples of "aback" in Sentences

But then they see the finished works and it really takes them aback, which is great. "
Options B and D are not correct as the word 'aback' means to get startled by something and does not means the same as the word 'back' which is used in the answer choices B and D.
As I read your stories and especially your friends who so generously comment I am taken aback (is aback a word?) by the generous sharing of wisdom you receive from your friends at French-Word-A-Day.
The richness and elegance of the church took me all "aback;" it was so entirely different from anything I had seen, that it was difficult to decide whether I was most charmed by its novelty or its beauty.
Hillary grew up in this culture, so yes she was taken "aback" by these comments; you, others, and obama being so shallow minded and dismissive of someones culture and values is ignorant. obama will never be President.