Not until he finished his work -------go home.A he did B did

选B。
Not until。。。和。。。not 。。。until。。。的意思都是一样的。用法上Not until 位于句首,主句采取部分倒装。部分倒装就是把谓语部分的操作词移到主语前。
结构是:Not until+从句/时间,主语(助动词/情态动词+主语+谓语的其他成分+其他)
Not until he finished his work did he go home。
(=He did not go home until he finished his work。)