The magnetic field at the orgini due to a current element `vec(idl)` placed at a point with vector position `vec(r)` is

Options

A. `(mu_(0) i)/(4 pi) (vec(r) xx vec(dl))/(r^(2))`
B. `(mu_(0)i)/(4pi) (vec(d)l xxvec(r))/(r^(3))`
C. `(mu_(0) i)/(4pi) (vec(r) xx vec(dl))/(r^(3))`
D. `(mu_(0)i)/(4pi) (vec(dl) xx vec(r))/(r^(2))`