单选题 This is the best book I have ever read on the subject, ______ there may be mistakes occasionally.
【正确答案】 B
【答案解析】[解析] for all that是复合连词,意为“尽管”。多用于口语,例如:I am sure he did it for all that he says he didn"t do it.(尽管他说,他没有做,但我相信他确实是做了。)