Final answer:
The correct antidote for anticholinergic poisoning by substances such as atropine or scopolamine is pilocarpine, which is a muscarinic agonist.
Step-by-step explanation:
The antidote for anticholinergic poisoning, such as that caused by atropine or scopolamine, is not atropine itself, physostigmine, ipratropium, or scopolamine. Instead, the correct antidote is pilocarpine, which is not included in the provided options. Pilocarpine acts as a muscarinic agonist which aids in counteracting the effects of anticholinergic substances like atropine by stimulating the parasympathetic nervous system that has been inhibited by the anticholinergic drug.