Sentence Correction

Q. A large and increasingly influential sector of publishing, 20 percent of all the National and American Book awards since 1950 have gone to university-press books.
(A) A large and increasingly influential sector of publishing, 20 percent of all the National and American Book awards since 1950 have gone to university-press books.
(B) A large and increasingly influential sector of publishing, university-press books have won 20 percent of all the National and American Book awards since 1950.
(C) Increasingly influential as a large sector of publishing, 20 percent of all the National and American Book awards since 1950 have gone to university-press books.
(D) Since 1950, a large and increasingly influential sector of publishing, 20 percent of all the National and American Book awards have gone to university-press books.
(E) Since 1950, university-press books, a large and increasingly influential sector of publishing, won 20 percent of all the National and American Book awards from then on.

OA is[spoiler] (B)[/spoiler]. Kindly answer with explanation. Also, what could be the difficulty level of this Q?

Thanks,
Rohit.