A, in the question, both handles do uniform circular motion, the linear velocity is tangent, and there are moments of anti-,co-and non-* * lines, so A is wrong;

B, the speed direction of the two handles is the same at two moments, and the arc on the left and right sides, so B is wrong;

C, the acceleration direction of the two handles has four moments in a straight line, the highest point, the lowest point, the leftmost point and the rightmost point, so c is wrong;

D, the two handles do uniform circular motion, and the linear speed, rotation radius and mass are all equal. According to the formula Fn=mv2r, the centripetal force is equal, so d is correct;

Therefore, choose: d.