What is the union of sets A and C?
U = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}, A = {1, 2, 3, 4, 5}, B = {0, 2, 4, 6, 8}, and C = {1, 3, 5, 7, 9}

1. A ∪ C = {0, 1, 2, 3, 4, 5, 6, 7, 9}

2. A ∪ C = {1, 2, 3, 4, 5, 7, 9}

3. A ∪ C = {0, 1, 2, 3, 4, 5, 6, 8}

4. A ∪ C = {1, 2, 3, 4, 5, 6, 7, 8, 9}