This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head and neck, Subject name: Anatomy
[{'content': 'Lacrimal punctum of upper and lower eyelid is \nSelect and explain. \nA. They are opposed, B. No relation, C. Upper punctum is medial, D. Upper punctum is lateral', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Each lacrimal canaliculus begins at the lacrimal punctum and is 10 mm long.it has a veical pa which is 2mm long and a horizontal pa which is 8 mm long. There is a dilated ampulla at the bend,both canaliculi open close to the each other in the lateral wall of the lacrimal sac behind the medial palpebral ligament. ref.BDC volume 3;sixth edition pg 76', 'role': 'assistant'}]