**Core Concept**
Belladonna poisoning is caused by the ingestion of Atropa belladonna, a plant containing the tropane alkaloids atropine and scopolamine. These alkaloids act as anticholinergic agents, blocking the action of acetylcholine at muscarinic and nicotinic receptors in the central and peripheral nervous system.

**Why the Correct Answer is Right**
The treatment of choice for belladonna poisoning involves administering an antidote that counteracts the anticholinergic effects of atropine and scopolamine. Physostigmine, a reversible cholinesterase inhibitor, is the specific antidote used to treat belladonna poisoning. It works by increasing the concentration of acetylcholine in the synaptic cleft, thereby overcoming the anticholinergic blockade caused by atropine and scopolamine.

**Why Each Wrong Option is Incorrect**
* **Option A:** Atropine itself is not an antidote for belladonna poisoning, as it would further exacerbate the anticholinergic effects.
* **Option B:** Gastric lavage and activated charcoal may be used as supportive measures, but they do not directly counteract the anticholinergic effects of atropine and scopolamine.
* **Option D:** Dopamine is not effective in treating belladonna poisoning, as it does not address the underlying anticholinergic blockade.

**Clinical Pearl / High-Yield Fact**
It's essential to note that physostigmine is not a first-line treatment and should only be used in severe cases of belladonna poisoning, as it can cause seizures and other side effects.

**Correct Answer:** C. Physostigmine