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: Pharmacology
Toxicity of nitrogen mustards can be decreased by 
Select and explain. 
A. Allopurinol, B. Folinic acid, C. GM-CSF, D. All
C: GM-CSF
Answer: C: GM-CSF 
Explanation: Ans. is `c GM-CSF o Nitrogen mustards and other alkylating agents can cause myelosuppression --> Leukopenia can be reversed by sargramostim (recombinant GM-CSF). o Haemorrhagic cystitis is more common with some (not all) nitrogen mustards, especially cyclophosphamide and ifosphamide, which is blocked by the use of MESNA or acetylcysteine. So, best option amongst the given options is 'c' (GM-CSF) as myelosuppression can be caused by all nitrogen mustard, whereas hemorrhagic cystitis is more common with cyclophosphamide and Ifosphamide.