For a current in a long straight solenoid N- and S-poles are created at the two ends. Among the following statements, the incorrect statement is 

The field lines inside the solenoid are in the form of straight lines which indicates that the magnetic field is the same at all points inside the solenoid 

The strong magnetic field produced inside the solenoid can be used to magnetize a piece of a magnetic material like soft iron when placed inside the coil 

The pattern of the magnetic field associated with the solenoid is different from the pattern of the magnetic field around a bar magnet 

The N- and S-poles exchange position when the direction of current through the solenoid is reversed