如图所示，吊在大厅天花板上的电风扇所受重力为G，静止时固定杆对它的拉力为F，扇叶水平转动起来后，杆对它的拉力产F^‘，则（     ）

A．F="G," F′=F	B．F="G," F′>F
C．F="G," F′<F	D．F′="G," F′>F