Question

which of the following supplements is also a naturally occurring hormone in the brain that is related to sleep? gingko biloba willow bark melatonin black cohosh

Explanation:

Melatonin is a hormone naturally produced in the brain by the pineal gland, and it plays a key - role in regulating the sleep - wake cycle. Gingko biloba is an herbal supplement for cognitive function, willow bark is for pain relief, and black cohosh is often used for menopausal symptoms.

Answer:

Melatonin