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: Pediatrics
[{'content': 'Most sensitive indicator of depletion of intravascular volume in infants is: \nSelect and explain. \nA. Cardiac Output, B. Stroke Volume, C. Hea Rate, D. Blood Pressure', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The most sensitive indicator of depletion of intravascular volume in infants is the hea rate. Ref: CURRENT Pediatric Diagnosis and Treatment, 18th Edition, Page 375; Practical Pediatrics, 5th Edition, Page 162', 'role': 'assistant'}]