问题

Though he is busy, music has always been _______ his work.[ ]
A: as much a part of his life as
B: as a part of his life much as
C: as much as a part of his life
D: so much a part of his life as
B: as a part of his life much as
C: as much as a part of his life
D: so much a part of his life as
正确答案是: