Who is the most popular classic composer?

The most popular classic composer is likely Ludwig van Beethoven. He is the composer of many enduring masterpieces of Western music, including the famous Fifth Symphony, Sixth Symphony (Pastoral), the Ninth Symphony (Choral) and his only opera, Fidelio. Additionally, he left his mark on several piano sonatas, including "Moonlight" and "Für Elise". He ranks amongst the most admired composers in the history of Western music.