Final answer:
Sleep facilitated creative thinking which allowed the nurse to solve the problem upon waking. This time away from active problem-solving allows the brain to process information differently, leading to insight.
Step-by-step explanation:
After a good night's sleep, a nurse wakes with a solution to a work-related problem. This likely occurred because sleep facilitated time for creative thinking. During sleep, the brain can consolidate memories, process learned information, and engage in problem-solving by reorganizing and making connections between ideas in ways that might not occur during waking hours when the mind is focused on immediate tasks. Thus, the answer to how sleeping helped the nurse solve the problem would be C. It was time for creative thinking.