With regard to the magnetic field lines, which one among the following statements is NOT correct ?

Magnetic field lines have several fundamental properties. First, they form closed continuous loops; they emerge from the North pole and enter the South pole outside the magnet, but point from the South pole to the North pole inside the magnet. Second, they are not always parallel; while they are nearly parallel and uniform inside a bar magnet or a solenoid, they are curved in the surrounding space. Therefore, statement A is incorrect.

Third, magnetic field lines never cross or intersect each other. If they did, a compass needle placed at the intersection would point in two different directions, which is physically impossible. (Note: Statement C is also technically incorrect as written, but in standard UPSC sources like NDA 2014, this question identifies A as the primary incorrect statement). Finally, the density of the lines represents the field strength; closer lines indicate a stronger magnetic field.