At a movie theater, the ticket prices to see a movie in 3-D are $18 for an adult and $12 for a child. The owner of the theater wants to make at least $300 when a movie is shown in 3-D. Choose the inequality that shows the numbers of tickets that must be sold. A. 18x + 12y > 300 B. 18x + 12y < 300 C. 18x + 12y ≥ 300 D. 18x + 12y ≤ 300