The sympathetic nervous system (S.N.S) work through secretion of
A. Noradrenaline, which stimulates the organ
B. Acetylcholine, which stimulates the organ
C. Adrenaline, which inhibits the organ
D. Both A and B

Hint: The sympathetic nervous system, which is an extensive network of nerves, is a part of the autonomic nervous system. It is accountable for the management of the involuntary operations of the body which prepares a person for a sudden emergency. During situations such as risk, assault, the nervous system gets triggered.

Complete answer: The body's sympathetic nervous system is triggered in response to acute stress. Increased heart rate, BP and breathing rate triggers the sympathetic nervous system. After 20 to 60 minutes, the body returns to its natural state. The sympathetic nervous system acts in response to neuronal and hormonal stress. The fight-or-flight type of response or sympathoadrenal type of response is often referred to as this type of response. The preganglionic sympathetic fibres produce this reaction. In the adrenal gland, these fibres stop. These fibres secrete acetylcholine, thus initiating adrenaline and noradrenaline activation and secretion. The muscles are activated by acetylcholine. Organs such as the heart and kidney are activated by adrenaline and norepinephrine. Thus, the S.N.S work through the secretion of noradrenaline and acetylcholine.
So, the correct answer is option D.

Note: Another part of ANS is the parasympathetic nervous system. One of the three branches of the autonomic nervous system is the parasympathetic nervous system. The parasympathetic system also called the rest and digest system, conserves energy as it reduces the heart rate, increases the activity of the intestines and glands, and relaxes the gastrointestinal tract's sphincter muscles.