Rewrite the Statement Using Mathematical Symbols $k$ And $z$ Is Not a Proper Subset Of

Rewrite the statement using mathematical symbols.
-The set consisting of the elements $k$ and $z$ is not a proper subset of $\{ c , f , z , u \}$ .

A) $\{ \mathrm { k } , \mathrm { z } \} \not \subset \{ \mathrm { c } , \mathrm { f } , \mathrm { z } , \mathrm { u } \}$
B) $\{ \mathrm { k } , \mathrm { z } \} \in \{ \mathrm { c } , \mathrm { f } , \mathrm { z } , \mathrm { u } \}$
C) $\{ \mathrm { k } , \mathrm { z } \} \subseteq \{ \mathrm { c } , \mathrm { f } , \mathrm { z } , \mathrm { u } \}$
D) $\{ k , z \} \sim \{ c , f , z , u \}$