问题：

[单选] Sidewise force of the propeller tends to throw a vessel’s stern to the right or left，depending on rotation. This force is caused by（）.

A . back current from the rudder
B . greater pressure on the right or left side of the propeller，depending on rotation
C . lower pressure on the right or left side of the propeller，depending on rotation
D . torque from the velocity and angle at which the surrounding water impinges upon the propeller blade