Which of the following can be a symptom of insomnia?

Struggling to fall asleep or stay asleep is indeed a hallmark symptom of insomnia. Individuals with insomnia often experience difficulty initiating sleep, maintaining sleep throughout the night, or waking up too early without being able to return to sleep. This can lead to feelings of frustration and anxiety around sleep, further exacerbating the problem.

In the context of insomnia, frequent daytime naps may occur as a coping mechanism, but they do not directly characterize the disorder itself. Sleeping more than eight hours regularly is typically indicative of sufficient sleep, which does not align with the experience of insomnia. Additionally, consistently waking up refreshed suggests that an individual is getting quality sleep, which contradicts the condition associated with insomnia. Hence, the aspect of struggling with sleep is crucial in understanding the symptoms associated with insomnia.