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: Physiology
[{'content': "Hamann's solution contains all of the following, EXCEPT: \nSelect and explain. \nA. Na++, B. Ca++, C. Mg++, D. Lactate", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Hamann solution is a crystalloid solution used for intravenous administration, it is also known compound sodium lactate. Hamann solution contains: Na+ 131 mmol/L Cl- = 111 mmol/L Lactate = 29 mmol/L K+ = 5 mmol/L Ca++ = 2 mmol/L pH = 6.5 Osmolarity = 279 mosm/L Ref: The ICU Book By Paul L. Marino, Page 237', 'role': 'assistant'}]