National's Improving Efficiency or Enterprise's Reorganizing Is a Sufficient and Necessary

Multiple Choice

National's improving efficiency or Enterprise's reorganizing is a sufficient and necessary condition for Thrifty's laying off workers, provided that Avis buys new cars.

A) (N ∨ E) ≡ (A ⊃ T)
B) A ⊃ [(N ∨ E) ≡ T]
C) [(N ∨ E) ≡ T] ⊃ A
D) A ⊃ [(N ⊃ E) • (E ⊃ N) ]
E) A ≡ [(N ∨ E) ⊃ T]