The ratio of chromium to iron to carbon varies
among the different types of stainless steel.
Therefore, stainless steel is classified as
(1) a compound (3) a mixture
(2) an element (4) a substance
The correct option is MIXTURE. Stainless steel is considered a mixture because it contains different elements which are mixed together in different proportions. The components of the stainless steel can also be separated by appropriate means.
