Show A ∪ Bᶜ = Aᶜ ∩ Bᶜ by demonstrating inclusion both ways.

a) A ∪ Bᶜ ⊆ Aᶜ ∩ Bᶜ and Aᶜ ∩ Bᶜ ⊆ A ∪ Bᶜ
b) A ∪ Bᶜ = Aᶜ ∩ Bᶜ
c) A ∪ Bᶜ ⊇ Aᶜ ∩ Bᶜ and Aᶜ ∩ Bᶜ ⊇ A ∪ Bᶜ
d) A ∪ Bᶜ ⊂ Aᶜ ∩ Bᶜ and Aᶜ ∩ Bᶜ ⊂ A ∪ Bᶜ