单项选择题

Why does the author suggest that the work of Beethoven was highly-creative

A.Because he adopted a new principle of organization in his work by utilizing innovative strategies.
B.Because he creatively manipulated the accepted rules and forms governing musical composition.
C.Because he synthesized a transition between the older stylistic convention and the newer musical form.
D.Because he sought to become the only composer of his time to challenge accepted musical conventions.