An electrodynamometer instrument has the advantage of

A)
low cost
B)
high torque/weight ratio
C)
freedom from hysteresis and eddy currents because air cored coils are used
D)
freedom from hysteresis and eddy currents because cores of coils have special ferromagnetic material

Correct Answer : Option (C) :   freedom from hysteresis and eddy currents because air cored coils are used