Answer:
The suprachiasmatic nuclei enable the nervous system to respond to daily light/dark alterations through their stimulation of melatonin.
Explanation:
Melatonin is a hormone produced naturally by the body. Its function is to regulate the body's circadian cycle. This hormone is stimulated and begins to act by changing between a light environment and a dark environment. This stimulation interacts with the suprachiasmatic nuclei making the nervous system understand this change and luminosity of the environment and respond to the action of melatonin.
I would say it's b.
stomach doesn't secrete lipase, only pancreas does.
stomach also doesn't manufactures bile, the liver does.
stomach contents are highly acidic , it's around pH 2.0 , which is completely opposite to alkaline