A vessel loads edible oil in a deep tank through a manhold at the midlength of the tank. In order to fill the tank to maximum capacity, what trim should the vessel have?（）.

A.Down by the bow

B.Down by the stern

C.Down by either the bow or stern

D.In level trim

关于提高加热炉热效率的途径，下列说法不正确的是（）。

A.增设烟道气余热回收系统

B.采用新型的加热炉炉墙材料

C.提高加热炉进风量

D.采用高效节能的新型火嘴