An unusual lightning strike has a vertical portion with a current of $-400$ A downwards. The Earth's magnetic field at that location is parallel to the ground and has a magnitude of $30T.$ In N $,$ the force exerted by the Earth's magnetic field on the $25$ m $-$long current is

a$.0.$

b$.0\mathrm{.}012$ N$,$ East.

c$.0\mathrm{.}012$ N$,$ West.

d$.0\mathrm{.}30$ N $,$ West.

e$.300$ N$,$ East.