This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Forensic Medicine
[{'content': 'In rigor mortis muscle - \nSelect and explain. \nA. Stiffens, B. Shortens, C. Stiffens and shortens, D. Stiffens and lengthens', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In rigor mortis there is contraction, stiffening, shortening and opacity of muscles after death.', 'role': 'assistant'}]