Which Rule Is Used in the Following Inference A)HS
B)MP
C)MT
D)CD
E)DD

Multiple Choice

Which rule is used in the following inference? $$\begin{array} { l } { [ ( Z \supset Y ) \cup ( Z \supset Y ) ] \supset [ \sim ( \sim A \cdot Z ) \supset ( \mathrm { X } \equiv Y ) ] } \\( Z \supset Y ) \cup ( Z \supset Y ) \\\sim ( \sim A \cdot \sim ) \supset ( \mathrm { X } \equiv Y ) \end{array}$$

A) HS
B) MP
C) MT
D) CD
E) DD