Answer: 1.
- A 0
- B 1
- C n
- D n!
Correct answer: B. 1
Explanation: nCn = 1. There is exactly one way to choose all items.
Counting tree for selecting 2 items from {A, B, C} without repetition: 3 x 2 = 6 ordered arrangements.
Concept context
Counting, arrangements, and selections