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: Pathology
[{'content': 'A 23 years old female presented with jaundice and pallor for 2 months. Her peripheral blood smear shows the presence of spherocytes. The most relevant investigation to arrive at a diagnosis is - \nSelect and explain. \nA. Retics count, B. Osmotic fragility test, C. Coombs test, D. Tests for PNH', 'role': 'user'}, {'content': 'Answer: C \nExplanation: . Coombs test', 'role': 'assistant'}]