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: Unknown
Which of the following is the most common adverse effect of LSD and its related substances? 
Select and explain. 
A. Bad trip, B. Flashbacks, C. Synaesthesia, D. Papillary dilatation
A: Bad trip
Answer: A: Bad trip 
Explanation: Most common adverse effect of LSD is BAD TRIP (Panic like reaction).