List All Subsets of the Given Set $$\{ Z , m \}$$

Multiple Choice

List all subsets of the given set. Identify any of the subsets that are improper. $$\{ Z , m \}$$

A) $\varnothing, \{ z \} , \{ m \} , \{ z , m \}$ Improper subset: $\varnothing$
B) $\varnothing , \{ z \} , \{ m \}$ Improper subsets: $\varnothing , \{ z \} , \{ m \}$
C) $\varnothing , \{ z \} , \{ m \} , \{ z , m \}$ Improper subset: $\{ Z , m \}$
D) $\varnothing , \{ z \} , \{ m \}$ Improper subsets: $\{ z \} , \{ m \}$
E) $\varnothing , \{ z \} , \{ m \} , \{ z , m \}$ Improper subsets: $\varnothing , \{ z \} , \{ m \} , \{ z , m \}$