两块长5d、相距d的水平平行金属板板间有垂直于纸面的匀强磁场，一大群电子从平行于板面的方向以相等大小的速度v从左端各处飞入，则为了不使任何电子飞出，板间磁感应强度的最小值为___________。

______ is expected, according to the online survey, is _______ prices of houses

will not go up an more.

A．What; that

B．As, that

C．It, what

D．Which, that