单项选择题

Topping wires fix the height of the derricks and （） to the deck may be used to prevent fore and aft movement.

A.stays
B.winches
C.barrels
D.brakes

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With reference to rules governing steering gear, which ...

单项选择题With reference to rules governing steering gear, which one of the following rules is incorrect? （）

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B.The auxiliary gear could be power operated in passenger ships
C.The auxiliary gear must be of adequate strength and sufficient to steer a ship at navigable speed
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船舶辅助机械

Topping wires fix the height of the derricks and （） to the deck may be used to prevent fore and aft movement.