Hint : The answer to this question is a metal which is soft but malleable. This element is highly used in making electrical wires due to its property of very high thermal and electrical conductivity.
Complete answer :
German silver contains these metals: Copper, Zinc and Nickel. It is an alloy containing approximately 50% Copper, 19% Zinc and 30% Nickel.
The alloy is silvery-white in colour. So, they named it initially Silver but as the alloy does not contain silver. This name was prohibited. It is a very hard and tough alloy. It is resistant to corrosion. This leads to its wide applications in tableware, marine fittings etc.
It is highly electrical resistant. This leads to its wide use in heating coils.
It further does not tarnish like silver and costs less.
It is highly lustrous. So, it is used in gift items.
Due to the varied composition of these three elements, they show various properties.
It is widely used as a base metal for silver-plated cutlery, zippers, key making, costume jewellery and for making musical instruments. It is even used in the production of coins. It is used further in marine fittings and plumbing fixtures because of corrosion resistance properties.
So, from the options given above; option b) Cu is the correct answer.
Note : The alloy may sometimes contain lead and tin. Another name for German silver is Nickel silver. Don’t get confused by the name German Silver and think that the alloy contains silver. It's name is given because of its shiny appearance. But it does not contain silver.