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': 'Best site to demonstrate capillary filling in infants – \nSelect and explain. \nA. Nail bed, B. Sternum, C. Ear lobule, D. Great toe', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The state of microcirculation can be assessed by capillary filling time (CFT)\nFirm pressure is applied over sternum or forehead by a ball of the thumb for 5 seconds. This leads to blanching.\nOn removal of pressure color returns. The time taken for complete return of color is designated as capillary filling time, the normal is less than or equal to 3 sec.\nProlonged CFT is the earliest sign signifying impairment or microcirculation.', 'role': 'assistant'}]