I hate stupid interview questions, like the one above. 
Other stupid interview questions include:
     "What’s your weaknesses and strengths?"
     "Who is your role model?"
And I got them all yesterday.
Imgine, you didn’t sleep at all the night before, then you have to drag yourself to their office and answer all these stupid questions.
What’s my greatest achievement?
How about "didn’t sleep last night, but still managed to get to your office this early on saturday, and looking amazing?"  (The "looking amazing" part wasn’t mine, a friend in elevator told me so:P)
But I went totally diplomatic and answered: "I am proud of all my achievements, but the greatest is yet to come",  and added, "what about yours?"
The interviewer was taken back and started to search for words at the back of his brain.
Then, "good question, I don’t know…" he looked puzzled and worried and switched to the next stupid question.
So, what’s your greatest achievement, my dear readers?