Correct Response: A. The rudder on the stern (rear) of a ship steers the ship by deflecting the stern to the left or the right. However, this deflection depends upon water flowing past the rudder. As the ship slows to a stop, the rudder becomes less and less effective for steering. When maneuvering a large ship up to a dock, side-mounted bow thrusters allow the bow (front) of the ship to be moved to the left or the right even when there is little or no forward motion. However, in most situations, minor directional adjustments (B) are best made using the rudder. Bow thrusters use fuel when they are operating (C); this is in addition to the fuel used when steering with a rudder. When on a relatively steady course such as a computer-controlled course (D), the rudder is the steering tool of choice.