**Core Concept**
Cobra envenomation leads to the release of neurotoxins that can cause muscarinic symptoms due to the inhibition of acetylcholinesterase, resulting in an accumulation of acetylcholine in the synapses. This causes excessive stimulation of muscarinic receptors, leading to symptoms such as salivation, lacrimation, urination, and defecation.

**Why the Correct Answer is Right**
The drug used to counteract these muscarinic symptoms is physostigmine, which is an anticholinesterase inhibitor. It works by inhibiting acetylcholinesterase, thereby preventing the breakdown of acetylcholine and increasing its availability for binding to muscarinic receptors. This helps to reverse the muscarinic symptoms caused by cobra envenomation.

**Why Each Wrong Option is Incorrect**
* **Option A:** Not relevant to muscarinic symptoms in cobra envenomation.
* **Option B:** Atropine is an antimuscarinic agent, which would worsen muscarinic symptoms.
* **Option C:** Not a specific antidote for muscarinic symptoms in cobra envenomation.

**Clinical Pearl / High-Yield Fact**
Physostigmine is a specific antidote for muscarinic symptoms caused by organophosphate poisoning and certain types of snake envenomation, such as cobra bite. It is essential to recognize the clinical presentation of muscarinic symptoms and use the appropriate antidote to manage these cases effectively.

**Correct Answer: C. Physostigmine**