The correct option is A noble
The word 'atrocious' refers to being horrifyingly wicked.
Option A, gracious refers to being courteous, kind and pleasant, especially towards someone of lower status.
Option B, noble refers to having or showing high moral qualities.
Option C, civilized refers to being polite and well mannered.
Option D, pleasing refers to feeling or showing pleasure or satisfaction.
Thus, according to the meaning, the word 'noble' is the opposite of the word 'atrocious'.