Auroras occur at of a planet. the equator the north magnetic pole only the south magnetic pole only both magnetic poles

The answer is - both magnetic poles

In the earth's southern magnetic pole, auroras are known as aurora austalis  or southern lights while in the northern magnetic pole they are known as aurora borealis or northern lights.

They are caused by charged particles borne in solar winds that are escaping from the sun. As they approach the earth,  the winds distort the earth's magnetic field which allows some particles to enter the earth's atmosphere, where they excite the gases and make them glow with spectacular display of colors.