Proposition 1H Given the Following Proposition

Multiple Choice

Proposition 1H
Given the following proposition:
[(A ≡ ∼B) ∨ (X ⊃ Y) ] • [(Y ⊃ A) ≡ ∼(X ∨ B) ]
-In Proposition 1H, the main operator is a:

A) Horseshoe.
B) Tilde.
C) Dot.
D) Triple bar.
E) Wedge.