This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Renal and Urinary Tract Disorders, Subject name: Gynaecology & Obstetrics
[{'content': 'Most common causative organism of acute pyelonephritis in pregnancy is? \nSelect and explain. \nA. E.coli, B. Klebsiella pneumonia, C. Enterobacter, D. Staphylococcus group', 'role': 'user'}, {'content': "Answer: A \nExplanation: ANSWER: (A) E.coliREF: Dutta's textbook of obstetrics 6th ed page 296Incidence of pyelonephritis in pregnancy 1-3%Previous history of urinary tract infection increases chance by 50%Organisms associated are: E:coli (70%), Klebsiella (10%), Enterobacter, Proteus pseudomonas, Staphylococcus aureus", 'role': 'assistant'}]