TTGWD31与最新13section,很多答案不一样，求助两道SC

Q2:

By merging its two publishing divisions, the company will increase their share of the country’s $21 billion book market from 6 percent to 10 percent, a market ranging from obscure textbooks to mass-market paperbacks.

1. their share of the country’s $21 billion book market from 6 percent to 10 percent, a market ranging
2. from 6 percent to 10 percent its share of the $21 billion book market in the country, which ranges
3. to 10 percent from 6 percent in their share of the $21 billion book market in the country, a market ranging
4. in its share, from 6 percent to 10 percent, of the $21 billion book market in the country, which ranges
5. to 10 percent from 6 percent its share of the country’s $21 billion book market, which ranges

  B VS E

Q16:

Soaring television costs accounted for more than half the spending in the presidential campaign of 1992, a greater proportion than it was in any previous election.

1. a greater proportion than it was

2. a greater proportion than

3. a greater proportion than they have been

4. which is greater than was so

5. which is greater than it has been

  B VS C

is anybody here?

E

B

can you explain in details....

for question no. 2, in B "which" refers to "country", wrong"
                

for question no. 16, "Soaring television costs" is plural form, all choices with "it" are wrong, plus the verb is "account for", using "have been" is wrong

"which" in DE can refer to either the "proportion of the spending" or "the presidential campaign"