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
Speedball is cocaine mixed with: NEET 13 
Select and explain. 
A. Heroin, B. Cannabis, C. Amphetamine, D. LSD
A: Heroin
Answer: A: Heroin 
Explanation: Ans. Heroin