The incorrect statement is:
Option: 1 Brass is an alloy of copper and nickel.
Option: 2 Dust iron is used to manufacture brought iron.
Option: 3 German silver is an alloy of zinc, copper and nickel.
Option: 4Bronze is an alloy of copper and tin
Brass is an alloy of copper and zinc, but not of copper and nickel. Thus, other statements are correct.
Therefore, Option(1) is correct.
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