Permanent magnetic materials

PERMANENT MAGNETIC MATERIALS

Q.Permanent magnetic material is/are
a) Niobium-titanium
b)Alnico
c)Barium ferrite (BaF12O19)
d)Somarium Cobalt (SmCo5)
e)Neodymium-ironboron (NdFeB)


ANS  ----BCDE,Niobium-titanium  is a semi-conductor