菜鸟求教一道语法题！

After the First World War,the author Anais Nin became interested in the art movement known as Surrealism and in psychoanalysis, both______her novels and short stories.

A.in which the influence

B.of which influenced

C.to have influence

D.its influence in

介词+which+完整句子，如果选B，both of which后面的句子不完整呀？多谢高手指教！

如果这样分析，后面的句子也是完整的，关键要注意有个both,   

从形式上可以这么看， （of which）both influenced her novels.......