If you are looking for one of his most famous compositions it would be, "Trauer" (Mourning) Symphony No. 44, "Farewell" Symphony No. 45, the Piano Sonata in C minor (Hob. XVI/20, L. 33), and the six "Sun" Quartets Op. 20, all from c. 1771–72.
Because the it did not agree with the union ideas so they said you have to change all of them if you want us to add your rules to the laws of the United States of America