This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Death and postmortem changes, Subject name: Forensic Medicine
Nysten's rule peains to - 
Select and explain. 
A. Rigor mois, B. Identification, C. Bullet injuries, D. Putrefaction
A: Rigor mois
Answer: A: Rigor mois 
Explanation: Nysten's rule states that Rigor mois does not sta in all muscles simultaneously, it appears first in involuntary muscles. Ref: K.S.Narayan Reddy's Synopsis of Forensic Medicine and Toxicology, 29th edition, Chapter 7, Page 88.