The Red River Valley is a sweet love song based upon a story that is anything____.
A. on B. but C. up D. around
谢谢“好题老师”又出“好题”了！
赞同Alex在评论中的说法，答案应该是 but。本来习语 anything but（绝不）后面应该接宾语的，由于 but 如此用时是介词。但，在语境明确的状况下，but后面的宾语有时也可以省略。譬如“韦氏”高阶的 anything 词条就有如此一句：
Though he said he was happy,he looked anything but . 尽管他说自己非常快乐，但他看着一点都不（快乐）。
