Sentence Correction

senthil wrote:The United States petroleum industry’s cost to meet environmental regulations is projected at ten percent of the price per barrel of refined petroleum by the end of the decade.
(A) The United States petroleum industry’s cost to meet environmental regulations is projected at ten percent of the price per barrel of refined petroleum by the end of the decade.
(B) The United States petroleum industry’s cost by the end of the decade to meet environmental regulations is estimated at ten percent of the price per barrel of refined petroleum.
(C) By the end of the decade, the United States petroleum industry’s cost of meeting environmental regulations is projected at ten percent of the price per barrel of refined petroleum.
(D) To meet environmental regulations, the cost to the United States petroleum industry is estimated at ten percent of the price per barrel of refined petroleum by the end of the decade.
(E) It is estimated that by the end of the decade the cost to the United States petroleum industry of meeting environmental regulations will be ten percent of the price per barrel of refined petroleum.



I feel the answer is A ... But still not convinced .. I feel in this case it shud be cost to .. so left with A,D,E .. ruling out D because 'by the end of decade ' is misplaced ...nw with A and E ...I feel 'of meeting environmental regulations ' is awkward so I ruled out E . But please explain if u find something wrong in my approach..

And cud someone let me know when to use cost of and cost to .. I am not that clear in this concept .. In the above sentences is there any chances of using cost of ?