A zoo charges $27 for adult tickets and $12 for child tickets. The average family spends at least $39 to go to the zoo. These charges can be represented by the inequality (27x + 12y ≥ 39). Which of the following is a viable solution in the context of the problem?
a. (4, -2)
b. (6, 3)
c. (0, 2)
d. (8, 2.5)