Rigor mortis is hastened in death following-
**Core Concept**
Rigor mortis is the stiffening of the body's muscles after death, caused by the breakdown of ATP and the resulting accumulation of actin and myosin filaments. This process is influenced by various factors, including the time elapsed since death, the body's temperature, and the presence of certain enzymes.
**Why the Correct Answer is Right**
The correct answer is related to the enzyme cathepsin, which plays a crucial role in the breakdown of actin and myosin filaments. Cathepsin is an acid protease that is involved in the degradation of muscle proteins, which in turn leads to the resolution of rigor mortis. When cathepsin is present in high concentrations, it accelerates the breakdown of muscle proteins, hastening the onset of rigor mortis.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option does not mention any specific enzyme or factor that would influence the onset of rigor mortis.
* **Option B:** This option is incorrect because adrenalin actually delays the onset of rigor mortis by stimulating the release of ATP from muscle cells.
* **Option C:** This option is incorrect because cold temperatures actually delay the onset of rigor mortis by reducing the activity of enzymes involved in the breakdown of muscle proteins.
**Clinical Pearl / High-Yield Fact**
Cathepsin is an acid protease that is involved in the degradation of muscle proteins, which in turn leads to the resolution of rigor mortis. This is an important fact to remember when performing autopsies or examining bodies in a forensic context.
**Correct Answer: D. Cathepsin.**