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
Which of the following immuno–suppressive agents acts selectively by inhibiting helper T–cells ? 
Select and explain. 
A. Cyclophosphamide, B. Azathioprine, C. Cyclosporine, D. Cystosine arabinoside
C: Cyclosporine
Answer: C: Cyclosporine 
Explanation: None