The material which is not suitable for producing a permanent magnet is given as,
A. steel
B. ticonal
C. lead
D. alnico

Hint: The magnetic property, if a material is the basic need for making the material a permanent magnet. The magnet should be having the property of attraction as well as repulsion. And the magnet should be having directive property also which means that the material should align perfectly in the north south direction when it is freely hanged. These all may help you to solve this question.

Complete step by step answer:
A fundamental stainless steel has a ferritic structure and it is magnetic also. This is due to the addition of chromium. Alnico is the family of a kind of alloys from which magnets are made. They are primarily made up of a combination of aluminium, nickel and cobalt. It can include elements like copper, iron and titanium. Alnico magnets have two versions. They are isotropic and anisotropic versions. Ticonal is the one of the trade names for the family of the alnico materials. Therefore they will also be magnetic materials. In the given materials lead is the only material which is not showing any kind of magnetic behaviour.

So, the correct answer is “Option C”.

Note: The magnetic properties of the stainless steel are very much dependent on the elements added into the alloy when we make it out. The magnetic behaviour of stainless steels will be changing in various magnitudes, ranging from the paramagnetic nature which is also known as the nonmagnetic nature in fully austenitic grades. It ranges up to hard or permanent magnetic nature in the hardened martensitic grades also.