This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anaesthetic equipments, Subject name: Anaesthesia
[{'content': 'Position for orotracheal intubation \nSelect and explain. \nA. Extension of neck and atlanto-occipital joint, B. Extension of only neck, C. Flexion of neck only, D. Flexion of neck and extension of atlanto-occipital joint', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Flexing of cervical joint at neck approx. 25-30degrees and extension of atlanto -occipital joint (head) approx. 85-110degrees enables oropharyngeal, pharyngolaryngeal and laryngotracheal axis in one line that allows easy intubation -This position is called as SNIFFING POSITION.', 'role': 'assistant'}]