A. their share of the country's $21 billion book market from 6 percent to 10 percent, a market ranging
Their is the incorrect pronoun
B. from 6 percent to 10 percent its share of the $21 billion book market in the country, which ranges
its is the correct pronoun, however which incorrectly modifies country instead of the book market.
C. to 10 percent from 6 percent in their share of the $21 billion book market in the country, a market ranging
Their is the incorrect pronoun
D. in its share,
...
Their is the incorrect pronoun
B. from 6 percent to 10 percent its share of the $21 billion book market in the country, which ranges
its is the correct pronoun, however which incorrectly modifies country instead of the book market.
C. to 10 percent from 6 percent in their share of the $21 billion book market in the country, a market ranging
Their is the incorrect pronoun
D. in its share,
...