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
Which of the following poisoning causes priapism and increased desire to pass urine? 
Select and explain. 
A. Snakebite, B. Ratti poisoning, C. Cantharide poisoning, D. Arsenic poisoning
C: Cantharide poisoning
Answer: C: Cantharide poisoning 
Explanation: Symptoms of cantharide poisoning: Burning sensation in the mouth and throat, followed pain in the stomach Severe thirst, difficulty in swallowing and speech Dull pain in the loins Scanty, and blood stained urine with increased desire to pass urine Priapism Prostration, convulsions and death Aboion in pregnant female Ref: Textbook of Forensic Medicine and Toxicology by K S Narayan Reddy, 27th edition, Page 490.