In a set of 15 aluminum castings, two castings are defective (D), and the remaining thirteen are good (G). A quality control inspector randomly selects three of the fifteen castings without replacement, and classifies each as defective (D) or good (G). Which of the following is NOT an elementary event for this experiment?
(D, D, G)
(G, D, G)
(G, G, G)
(D, D, D)
The probability of an elementary event is determined. Defective aluminum casting is analyzed.