This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Orbit, Subject name: Ophthalmology
[{'content': 'Negative Jones-1 and jones-II Dye test indicate \nSelect and explain. \nA. Primary Hypersecretion of tears, B. Partial obstruction of distal nasolacrimal duct, C. Lacrimal pump failure, D. Partial obstruction of lacrimal canaliculi', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. (c) Lacrimal pump failureRef: Kanski 8/e, p. 67, 68* Partial obstruction of proximal lacrimal passages (Punctal or canalicular) or pump failure- Negative Jones 2* Partial obstruction of the nasolacrimal duct distal to the sac-Positive Jones, 2.', 'role': 'assistant'}]