**Core Concept**
The venom of kraits, a genus of venomous snakes, contains a complex mixture of bioactive compounds, primarily neurotoxins that target the nervous system. These neurotoxins are responsible for the clinical manifestations of krait envenoming, which primarily affect the nervous system.

**Why the Correct Answer is Right**
The venom of the krait, specifically the Indian krait (Bungarus caeruleus), contains a potent neurotoxin called notexin, which is a phospholipase A2 enzyme. Notexin acts by disrupting the function of the nervous system, particularly at the neuromuscular junction, by inhibiting the release of acetylcholine and preventing its binding to nicotinic acetylcholine receptors. This results in flaccid paralysis and respiratory failure if left untreated.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not accurately describe the primary composition or mechanism of krait venom.
* **Option B:** This option is incorrect because it is not a known component of krait venom and does not accurately describe its mechanism of action.
* **Option C:** This option is incorrect because it is not a correct description of the primary effect of krait venom on the nervous system.

**Clinical Pearl / High-Yield Fact**
The Indian krait is responsible for a significant proportion of snakebite-related deaths in India, often due to delayed medical treatment and the lack of effective antivenom.

**Correct Answer: C. Neurotoxin**