Nickel shows ferromagnetic property at room temperature. If the temperature is increased beyond Curie temperature, then it will show:
A. Paramagnetism
B. Anti-Ferromagnetism
C. NO magnetic property
D. Diamagnetism

Hint If the temperature of a ferromagnetic material is raised above a certain value, called the Curie temperature, the coupling ceases to be effective. Due to which magnetic moments of the electrons reduce.

Complete Step By Step Answer
Nickel exhibits ferromagnetism due to a quantum physical effect called exchange coupling in which electron spins of one atom interact with those of neighboring atoms.
The result is alignment of the magnetic dipole moments of the atoms, in spite of the randomizing tendency of atomic collisions. This persistent alignment is what gives ferromagnetic materials their permanent magnetism.
Most such materials then become simply paramagnetic, that is the dipoles still tend to align with an external field but much more weakly, and thermal agitation can now more easily disrupt the alignment.
 When temperature increases then magnetic fields inside the matter decreases because the magnetic moment of electrons get randomised direction due to temperature changes.
Finally a condition comes when the magnetic moment of electrons gets reduced to a particular stage which is called paramagnetism.
And the temperature above which ferromagnetic materials get converted into paramagnetic is called curie temperature.

Hence the correct option is ( A) Paramagnetic.

Note Ferromagnetism is a physical phenomenon in which certain electrically uncharged materials strongly attract others.
Paramagnetism is a form of magnetism whereby some materials are weakly attracted by an externally applied magnetic field.