Piaget and Nautica Do Not Have a Sapphire Watch Unless

Multiple Choice

Piaget and Nautica do not have a sapphire watch unless Breitling's having a diamond watch is a sufficient and necessary condition for either Cartier's offering multiple dials or Gucci's selling a self-winder.

A) ∼(P • N) ∨ [(C ∨ G) ≡ B]
B) (∼P • ∼N) ∨ [(B ⊃ C) • (G ⊃ B) ]
C) (∼P • ∼N) ∨ [(B ≡ (C ∨ G) ]
D) (∼P • ∼N) ⊃ [(B ≡ (C ∨ G) ]
E) [(B ≡ (C ∨G) ] ⊃ (∼P • ∼N)