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: Unknown
Stroke volume can be decreased by which of the following? 
Select and explain. 
A. Increasing ventricular contractility, B. Increasing heart rate, C. Decreasing total peripheral resistance, D. Decreasing systemic blood pressure
B: Increasing heart rate
Answer: B: Increasing heart rate 
Explanation: Stroke volume is determined by preload, afterload, and contractility Increasing heart rate decreases the time for filling during diastole and may decrease preload and therefore stroke volume. Increasing preload by increasing central venous pressure will increase stroke volume. Similarly, decreasing afterload by decreasing total peripheral resistance or systemic blood pres sure will cause an increase in stroke volume, Increasing contractility will also increase stroke volume.