在鼻腔的血液供应中，鼻腭动脉直接分支于（）。

A.眼动脉

B.筛前动脉

C.上颌动脉

D.蝶腭动脉

E.眶下动脉

（）The main center-line structural member, running fore and aft along the bottom of a ship, sometimes referred to as the backbone.

A.Frame

B.Deckbeam

C.Stringer

D.Keel