I → Intensity of magnetization
H → Magnetic intensity

(A) (a) is steel, (b) is soft iron
(B) retentivity of (b) > (a)
(C) (a) is used to make temporary magnets
(D) (b) can be easily demagnetised

Which of the given statements are correct?

(A), (B) and (D)

Soft iron: low coercivity and small hysterisis loss. It can be easily magnetised and demagnetised.

Steel: High coercivity and large hysteresis loss. It cannot be easily magnetised and demagnetised.

A magnet can be completely demagnetized only by applying a reverse field equivalent coercivity of the material.