It's not incorrect, it's partially correct. he asked where can I find THE Master Ball, as in the Master Ball that is given to you during the story. You could have commented on my answer that it's also found in the glowing spots in Cerulean Cave and i would have added it to my answer. Downvoting my answer and then adding an answer of your own is very point-grubby. Now I could convert your answer into a comment but ill choose to take the high road, i wont even downvote you.