According to the passage, boutique beers wouldn't have exploded in the United States if which of the following happened? ( )

参考解析：

推理题。题干中用了一个虚拟语气的结构，由would have done结构可知是过去情况的虚拟。我们首先要读懂题干问得是什么：根据本文，如果发生了下列哪件事情，精品啤酒也就不会在美国风行了。换句话说精品啤酒之所以在美国流行是因为下面哪一件事。根据题干关键词boutique beers和the United States迅速定位到原文第二段第一句话：Over the past decade, varieties once thought of as boutique beers, such as I.P.A s, have exploded in the United States, thanks to the relocate movement以及后面的关键内容：Since craft brewers use about ten times more hops than mega brewers, the trend has been a bonanza for Steinway and the other big hops companies.由此可推测出：精品啤酒在美国风行的原因是小型酿酒商与大型酿酒商所用的啤酒花的类型不同，所以反退回去，要是使用的啤酒花类型相同，精品啤酒很难流行，所以正确答案选C。A、B、D三项原文均未提及。