As a busy rock musician, managing his scheduling and negotiating

(A) As a busy rock musician, managing his scheduling and negotiating were made much easier by having a top notch agent.

The modifier As a busy rock musician n seems to modify managing, conveying that managing is a rock musician. Alternatively, As a busy rock musician modifies nothing, as no person is mentioned. Also, depending on how you read the sentence, possibly were should be the singular was, because managing is the subject.

(B) As a busy rock musician, having a top notch agent made managing his scheduling and negotiating much easier.

As a busy rock musician has to modify some noun. In this version it either modifies nothing or modifies having a top notch agent, conveying a nonsensical meaning either way.

(C) Being a busy rock musician and having a top notch agent, managing his scheduling and negotiating was made much easier.

This one is even worse. It starts with a modifier that modifies nothing, and also the connection between having a top notch manager and managing being made easier is not clearly conveyed.

(D) A busy rock musician, he made managing his scheduling and negotiating much easier by having a top notch agent.

This one correctly conveys a clear meaning, and begins with an appositive, A busy rock musician, which clearly modifies he.

(E) Busy as a rock musician, he made scheduling and negotiating management much easier by having a top notch agent.

This one is fixes the modifier issue seen in the original, but Busy as a rock musician does not convey a clear meaning. Is he as busy as a rock musician? or is he a busy rock musician? Also, scheduling and negotiating management is a little awkward, and does not clearly convey that he made scheduling and negotiating management easier for himself.

The correct answer is .