单项选择题
如图所示,直杆受扭转力偶作用,在截面1—1和2—2处的扭矩为:()
A.5kN·m,5kN·m B.25kN·m,-5kN·m C.35kN·m,-5kN·m D.-25kN·m,25kN·m
A.2τ B.4τ C.8τ D.16τ
A.A B.B C.C D.D