Four distinct keys are placed randomly on a circular key ring. What is the probability that two specific keys (Key A and Key B) always remain next to each other?

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A 1/3
B 2/3
C 1/2
D 1/4

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Answer: B. 2/3

Circular arrangements of 4 keys = (4 - 1)! = 6.
Treat A and B as one unit: (3 - 1)! × 2 = 4 arrangements with A and B together.
Probability = 4/6 = 2/3.

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Four distinct keys are placed randomly on a circular key ring. What is the probability that two specific keys (Key A and Key B) always remain next to each other?

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