【正确答案】 D

【答案解析】文章的最后一句是“To boost revenue，search engines in the past year have been accepting payments from businesses interested in receiving a higher ranking in certain categories or ensuring that their sites are reviewed more frequently．”这句话的意思就是“为了增加收入，搜索引擎在过去几年里接受了一些公司的资助，这些都是想在同类中提高地位或者愿意使网站被人们经常浏览的公司”。所以说资助搜索引擎的公司的目的就是让自己的网站被上网者多多浏览。所以答案是D。