The statement that accurately describes magnetic fields is:
Field lines are denser where the magnetic field is strongest.
This statement is true because denser field lines indicate a stronger magnetic field in that region.
The other statements are incorrect:
- Magnetic fields can affect both charged objects and magnetic materials, not just objects with charge.
- Magnetic fields are actually strongest near the poles of a magnet, not weakest.
- Field lines point from the north pole to the south pole of a magnet, not the other way around.