This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Forensic Toxicology - Concepts, Statutes, Evidence, and Techniques, Subject name: Forensic Medicine
Putrefaction is delayed in which poisoning? 
Select and explain. 
A. Lead, B. Arsenic, C. Mercury, D. Copper
B: Arsenic
Answer: B: Arsenic 
Explanation: ANSWER: (B) ArsenicREF: Parikh 6tK edition page 3.26Putrefaction is delayed in poisoning of:ArsenicAntimonyCarbolic acidStrychnine (Nux vomica)Zinc oxideAlso know:Rate of putrefaction in different medium is determined my (Casper's Dictum) AIR > WATER > EARTH (8:2:1)First internal sign of putrefaction is "Greenish discoloration of under surface of liver"First external sign of putrefaction is "Greenish discoloration of flank over caecum"Larynx & Trachea is first organ to putrefyBone is the last tissue to putrefyProstate and non-gravid uterus are relatively resistant to putrefaction (last to putrefy if bone is not available in options)