This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Heart, Circulation, and Blood, Subject name: Physiology
Cardiac output decreases during 
Select and explain. 
A. Moderate increase in environmental temperature, B. Anxiety and excitement, C. Eating, D. Standing from lying down position
D: Standing from lying down position
Answer: D: Standing from lying down position 
Explanation: Ans. (d) Standing from lying down positionRef: Ganong, 25th ed/p.544Cardiac output changesNo change:SleepIncreases during:Anxiety and excitement (50-100%)Eating (30%)Exercise (up to 700%)High environmental temperaturePregnancyEpinephrineDecreases during:Standing from lyingHeart diseases