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• Lightning conductors (usually made of copper) are installed at the topmost parts of buildings to create an electric field that attracts lightning discharges towards themselves rather than allowing the discharge to strike the building directly. Thus, statement 1 is correct. • These conductors safely carry the electric discharge deep into the earth, preventing damage to the structure. Thus, statement 2 is correct. • However, the conductivity of the earth is higher, not lower, than that of a building material, so statement 3 is incorrect. • Lightning conductors are installed at the highest point on buildings to offer a path of least resistance for the discharge, thus statement 4 is correct. Thus, the correct answer is (c) 1, 3, and 4.
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