'Flash-back' phenomenon is seen with the use of -: (A) Cannbis, (B) Psilocybin, (C) LSD, (D) All of the above
Answer is D. Flash-back is the spontaneous occurrence of previously experienced drug effects without taking the drug at the moment. Flash-back is usually associated with hallucinogens (LSD, Psilocybin, psilocin) and occasionally with cannabis (marijuana).