Complex sentence: The Symphony No.28 in C major KV 200/189k was composed by Wolfgang Amadeus Mozart, if it is from 1774, it is his last piece in the "Salzburg series".
Split into simpler sentences: The Symphony No.28 in C major KV 200/189k was composed by Wolfgang Amadeus Mozart. Likely composed in 1774, it is his last piece in the "Salzburg series".