The dipole moment of a circular loop carrying a current I, is m and the magnetic field at the centre of the loop is `B_(1)`.When the dipole moment is doubled by keeping the current constant, the magnetic field at the centre of the loop is `B_(2)`. The ratio `B_(1)//B_(2)` is

Options

A. `sqrt(2)`
B. `(1)/(sqrt(2))`
C. 2
D. `sqrt(3)`