If A = {a, b}, B = {2, 3, 5, 6, 7} and C = {5, 6, 7, 8, 9}, find A × (B ∩ C).

• A
• ϕ
• {(5, a), (6, a), (7, a), (5, b), (6, b), (7, b)}
• {(a, 5), (a, 6), (a, 7), (b, 5), (b, 6), (b, 7)}