Answer:
D.magnetic field of earth
Step-by-step explanation:
Magnetic compass is having a magnetic needle in it.
This magnetic needle will deflect in the direction of the magnetic field where it is placed
So when we place the magnetic needle or compass at any place on the Earth surface it always shows the Northern direction.
It is because our Earth has its own magnetic field which will apply torque on the magnetic needle due to which the needle will align itself into the direction of field.
So here the correct answer will be
D.magnetic field of earth