A square loop of side `L` carries a current `I`. Another smaller square loop of side `l(l lt lt L)` carrying a current `i` is placed inside the bigger loop such that they are coplanar with their centre coinciding. If the currents in the loops are in the same direction, the magnitude of the torque on the smaller loop is
A. `(mu_(0)Iil^(2))/(sqrt(2)piL)`
B. `(mu_(0)Iil^(2))/(2piL)`
C. `(mu_(0)Iil^(2))/(sqrt(3)2piL)`
D. Zero