A rod is free to rotate about its mid point. If the clockwise moments of 17 N m and 25 N m, respectively, are acting at the two ends of the rod, then the net moment acting on the rod is
A. 42 N m , anti-clockwise
B. 42 N m, clockwise
C. 8 N m, anti-clockwise
D. 8 N m, clockwise
