— How was your visit to the Green Expo Garden？

— Wonderful! We enjoyed          very much during the whole trip.

A．itself

B．myself

C．yourselves

D．ourselves

自动舵一般由偏航检测、信号比较、信号放大、执行机构和反馈等主要机构组成，其中检测船舶偏航的元件是（）

A.GPS导航仪；

B.标准罗经；

C.磁罗经；

D.陀螺罗经。