An “aberration” means a departure from what is normal, usual, or expected, typically an unwelcome one.
Option A is the correct answer because a “deviation” means a departure from what is normal, hence it is the correct meaning for the given word.
Option B is incorrect because “steadfastness” means the quality of being dutiful and unwavering, which is incorrect because it is not the same as an aberration.
Option C is incorrect because “privilege” means a special right, advantage granted or available only to a particular person or group, which is not the correct meaning for the given word.
Option D is incorrect because procrastination means to delay a task due to laziness or other reasons which is not the correct meaning for the given word. Hence it is incorrect.