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: Biochemistry
Azathioprine is used as 
Select and explain. 
A. Immunosuppressant, B. Antigout drug, C. Anti-retro virus, D. Anti- cancer
A: Immunosuppressant
Answer: A: Immunosuppressant 
Explanation: CompoundUseNucleoside analogueBromodeoxyuridineaStudy cell proliferationThymidine analogueAllopurinalAnti gout drugHypoxanthine analogueAzathiopineImmunosuppressantPurine analogue