**Core Concept**
Delayed rigor mortis refers to a phenomenon where the onset of rigor mortis, or the stiffening of the body after death, is delayed beyond the typical 2-4 hours. This can be caused by various factors, including certain types of poisoning.

**Why the Correct Answer is Right**
Delayed rigor mortis is commonly associated with poisoning by **sodium channel blockers**, such as **organophosphates**. These substances inhibit the release of acetylcholine from nerve terminals, leading to an accumulation of acetylcholine in the neuromuscular junction. This results in an initial flaccidity of the muscles, followed by a delayed onset of rigor mortis. The mechanism behind this phenomenon is related to the disruption of normal neurotransmitter release and the subsequent effects on muscle contraction.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not relevant to the phenomenon of delayed rigor mortis.
* **Option B:** This option is incorrect because it does not accurately describe the mechanism behind delayed rigor mortis.
* **Option D:** This option is incorrect because it is not a known cause of delayed rigor mortis.

**Clinical Pearl / High-Yield Fact**
It is essential to note that delayed rigor mortis can also be caused by other factors, such as **hypothermia** or **chemical burns**. In these cases, the mechanism is not related to sodium channel blockers, but rather to the disruption of normal cellular function.

**Correct Answer:** C. Organophosphate poisoning.