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
Nitroglycerine exerts beneficial effects in classical angina pectoris primarily by: 
Select and explain. 
A. Increase in total coronary blood flow, B. Redistribution of coronary blood flow, C. Reduction of cardiac preload, D. Reduction of cardiac afterload
C: Reduction of cardiac preload
Answer: C: Reduction of cardiac preload 
Explanation: None