Final answer:
The best solution for Sarah's trouble sleeping is establishing a regular sleep schedule and practicing relaxation techniques, as these actions help regulate melatonin levels and promote better sleep.
Step-by-step explanation:
To address Sarah's sleeping problems, according to the "Neurons and Neurotransmitters" lecture, the most beneficial solution would be d) Establishing a regular sleep schedule and practicing relaxation techniques. This is because melatonin, an amine that affects the sleep-wake cycle, is produced in higher levels as light decreases, promoting drowsiness.
Exposing oneself to natural light during the day and avoiding bright lights before bedtime can help regulate the sleep-wake cycle. Additionally, avoiding stimulants such as caffeine before bed, engaging in relaxation techniques, and maintaining a consistent sleep schedule can support healthy sleep patterns. Taken together, these practices help maintain steady melatonin levels and promote the onset of sleep.