This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Poisoning, Subject name: Forensic Medicine
Caustic poison erodes mucosa because - 
Select and explain. 
A. Glue like action, B. Hygroscopic in nature, C. High affinity for mucosa, D. Being programmed to stick
B: Hygroscopic in nature
Answer: B: Hygroscopic in nature 
Explanation: caustic soda is sodium hydroxide * In concentrated form, alkali acts as corrosive and in dilute form they act as irritant strong alkalis absorbs water from tissues and precipitates protein * Strong alkali produces liquefaction necrosis and causes saponification of fats and dissolves proteins thus causing deep penetration in the tissue resulting in extensive tissue destruction REF;THE SYNOPSIS OF FORENSIC MEDICINE:KS NARAYANA REDDY;28th EDITION;PAGE NO302