It is implied in the passage that ______.

A．the Maces believe a good career is even more important than their family life

B．Rodney's children are quite happy with the family situation

C．either a husband or a wife has to sacrifice his or her career for a firm family tie

D．the practice of sharing household jobs between husband and wife is commonplace in London

在一张日历表中，用正方形圈出4个数，这4个数的和可以是78吗？简要说明你的理由．