Answer: 15.
- A 12
- B 15
- C 30
- D 6
Correct answer: B. 15
Explanation: 6C2 = 15. Order does not matter (just choosing, not arranging).
Counting tree for selecting 2 items from {A, B, C} without repetition: 3 x 2 = 6 ordered arrangements.
Concept context
Counting, arrangements, and selections