This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: New born infants, Subject name: Pediatrics
[{'content': 'Size of tracheal tube in a newborn weighing 2.5kg is \nSelect and explain. \nA. 2, B. 3, C. 4, D. 5', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Guidelines for Tracheal Tube Size and Depth of InseionTUBE SIZE (MM INTERNAL DIAMETER)DEPTH OF INSEION FROM UPPER LIP (cm)WEIGHT (g)GESTATION (wk)2.56.5-7<1,000<2837-81,000-2,00028-343/3.58-92,000-3,00034-383.5/4.0>=9>3,000>38Ref: Nelson; 20th edition; Page no: 846', 'role': 'assistant'}]