GWD-31-Q30

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.    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.

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.     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.

答案：B。请问下这道题C有什么语法错误吗？B读起来确实很顺口，但是B把原句中的projected换成了estimated，实意动词都能换，这是为什么呢？请nn多多指教！

刚查了前人的帖子，知道cost to sb.of doing sth.是个固定搭配。而且B选项的cost用的是动词形式，而C用的是名词形式，从这点上考虑B比C好。而且B避免了头重脚轻的句子结构。但是我实在不明白的是B怎么可以把projected换成了estimated的呢？请nn多多指教！