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
First change in a dead body: 
Select and explain. 
A. Mummification, B. Greenish discolouration of RIF, C. Putrefaction, D. Maggot formation
B: Greenish discolouration of RIF
Answer: B: Greenish discolouration of RIF 
Explanation: Greenish discolouration of RIF