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 is NOT a direct acting anti-platelet agent? 
Select and explain. 
A. Aspirin, B. Clopidogrel, C. Atorvastatin, D. Alteplase
C: Atorvastatin
Answer: C: Atorvastatin 
Explanation: Atorvastatin