Final answer:
Positive reinforcement for increasing staff motivation is best represented by giving on-the-spot recognition to an employee for accomplishing a goal, as it encourages ongoing good performance.
Step-by-step explanation:
The action that would demonstrate positive reinforcement with the goal of increasing staff motivation is giving spur-of-the-moment recognition to an employee who has accomplished a goal. This type of reinforcement is effective because it is unexpected and therefore can encourage continuous good performance, as employees are aware that at any moment their efforts could be recognized. In comparison, thanking employees every morning regardless of performance (option a), rotating an award among all employees (option b), and waiting for an annual review (option c) do not provide the same immediate, performance-linked reinforcement.