My ruler is longer than -----?

选A。因为这里要用 名词性物主代词 。我的尺子比他的（她、你的）长,后边是人,就应该用宾格,那么主格:I you he she you we they 宾格:me you him her you us them 形容词性物主代词:my your his her your our their 名词性物主代词:mine yours his hers yours ours theirs 只能在最后里边挑一个最合适的,就是his。