Simplify the following text for a Grade 8 native English-speaking person.
Original: In the Baroque period , D major was seen as `` the key of glory '' ; so many trumpet pieces were in D major . Examples include concertos by Fasch , Gross , Molter ( No. 2 ) , Leopold Mozart , Telemann ( No. 2 ) , and Giuseppe Torelli ; sonatas by Corelli , Franceschini , Purcell , Torelli ; and `` The Trumpet Shall Sound '' and the `` Hallelujah '' chorus from Handel 's Messiah .
Simplified: In the Baroque period , D major was regarded as `` the key of glory '' ; hence many trumpet concertos were in D major , such as those by Fasch , Gross , Molter ( No. 2 ) , Leopold Mozart , Telemann ( No. 2 ) , and Giuseppe Torelli .