Which of the following best describes magnetic fields

Well the multiple choices for this question would be helpful, but from my own knowledge I would say:

Magnetic fields have north and south magnetic poles.

Magnetic fields have various characteristics which includes; they originate from the north poles and flow towards the south poles, they are exhibited in the form of magnetic field lines. Magnetic fields lines never cross one another,they all have the same strength and seek the path of least resistance between opposite magnetic poles etc.

why is arctic sea ice important? arctic sea ice keeps the polar regions cool and moderate global climate. sea ice has a bright surface; 80 percent of the sunlight that strikes it is reflected back into space. as sea ice melts in the summer, it exposes the dark ocean surface.