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: Psychiatry
Formication and delusion of persecution occurs together in intoxication with which of the following? 
Select and explain. 
A. Cocaine, B. Amphetamine, C. Cannabis, D. LSD
A: Cocaine
Answer: A: Cocaine 
Explanation: Formication is a type of tactile hallucination, in which patient feels that insects or bugs are crawling under his skin. Such type of hallucination is seen in case of cocaine intoxication (cocaine bugs). Delusions of persecution can be seen in cannabis, amphetamine as well as cocaine intoxication or psychosis induced by these substances. A combination of formication and delusion of persecution is seen in cocaine abuse.