Beethoven's greatest composition?

They are all great, but most may say the 9th symphony is the greatest. It is my favorite symphony of his, but I love his sonatas. Nobody beats him in sonatas. Mozart would be next, then Bach as musicians that is. Bach made fugues a lot, but Beethoven is the master of the piano. Bach didn't have a piano in his time. I guess the 9th, although the 5th is the most famous symphony ever. Everyone knows it and knows who made it and the number of it-5! Between the 5th and the 9th? For me the 9th!