单项选择题
A support produces ( ) in a particular direction on its attached member if it prevents ( ) of the member in that direction, and it produces ( ) on the member if it prevents ( ).
A．an external force, translation, an external couple moment, rotation
B．an internal force, translation, an internal couple moment, rotation
C．an internal force, movement, a couple moment, translation
D．an external force, translation, an internal couple moment, translation
