选 B
这是现在分词做状语.属于非谓语形式.
从他的口音判断,他一定是南方人.
这个比较特殊,本来是表示被判断的,一般用过去分词.但这里是用现在分词,主动的,固定搭配.
judging from.从.判断
judging from/by 由.判断,judging from 用作独立结构,即不用考虑从句和主句逻辑关系的一致性,用法相当与:generally speaking,considering (考虑到)
例如:judging from the truth,he is honest enough.
2.judging from the view,the earth is round.