Which one among the following correctly defines a unit magnetic pole in SI units?
It is the pole which when placed in air at a distance of

Options

A. 1 foot from an equal and a similar pole repels it with a force of 1 pound
B. 1 metre from an equal and a similar pole repels it with a force of 1 newton
C. 1 cm from an equal and a similar pole repels it with a force of 1 dyne
D. 1 metre from an equal and a similar pole repels it with a force of 1 newton/`m^2`