Let $A, B, C$ and $D$ be four nonempty sets. The contrapositive of 'if $A \subseteq B$ and $B \subseteq D$ then $A \subseteq C$' is

• A
  If $A \nsubseteq C$,then $A \nsubseteq B$ or $B \nsubseteq D$
• B
  If $A \subset C$,then $A \subseteq B$ and $B \subseteq D$
• C
  If $A \subseteq C$,then $A \subseteq B$ and $B \subseteq D$
• D
  If $A \subseteq C$,then $B \subset A$ or $D \subset B$