The schematic diagram is depicting some features of autonomic and somatic nervous systems. The neurotransmitter at site 'F' is
Acetylcholine
Norepinephrine
Dopamine
Epinephrine
Acetylcholine (ACh) is the primary transmitter at ANS ganglia and at the somatic neuromuscular junction .Katzung Pharmacology 12th edition Pg: 80
Autonomic nervous system