Rank the following materials from highest to lowest electrical conductivity at 25∘C.
(1) Brass (substitutional alloy of Cu and Zn)
(2) Steel (interstitial alloy of Fe and C)
(3) Graphite
(4) Solid NaCl
Which ranking is correct?
a) (1)>(3)>(2)>(4)
b) (1)>(2)>(3)>(4)
c) (3)>(1)>(2)>(4)
d) (1)>(2)>(4)>(3)