[求助]天山-4-2

Twenty years ago, Balzania put in place regulations requiring operators of surface mines
to pay for the reclamation of mined-out land. Since then, reclamation technology has not
improved. Yet, the average reclamation cost for a surface coal mine being reclaimed
today is only four dollars per ton of coal that the mine produced, less than half what it
cost to reclaim surface mines in the years immediately after the regulations took effect.
Which of the following, if true, most helps to account for the drop in reclamation costs
described?
A. Even after Balzania began requiring surface mine operators to pay reclamation
costs, coal mines in Balzania continued to be less expensive to operate than coal
mines in almost any other country.
B. In the twenty years since the regulations took effect, the use of coal as a fuel has
declined from the level it was at in the previous twenty years.
C. Mine operators have generally ceased surface mining in the mountainous areas of
Balzania because reclamation costs per ton of coal produced are particularly high
for mines in such areas.

The answer is C but I think the answer is B

因为C中说generally ceased那不是就没有reclamation的成本了吗??而不是像题目说的现在的成本比以前少

for your reference

http://forum.chasedream.com/dispbbs.asp?boardID=24&ID=84506&page=1

但我还是认为b比较好…..我是那里想错了吗??

B is unrelated to the argument.

The use of coal as a fuel does not have a definite relationship with the cost of the reclamation. Especially, the passage do not mention this relationship.