A drug X reverses the actions produced by parasympathetic nervous system in the body but is not able to reverse the actions of exogenously administered acetylcholine in in-vitro experiments. The mechanism of drug X can be
High-Yield Explanation
Muscarinic receptor antagonist and agonists acts on receptor. Acetylcholine esterase inhibitor inhibits acetylcholinesterase enzyme leading to increase in the levels of acetylcholine. Inhibitor of release of acetylcholine will inhibit the release of endogenous acetylcholine from synaptic vesicles. This will not interfere with exogenously administered acetylcholine.