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: Gynaecology & Obstetrics
[{'content': 'Triradiate pelvis is seen in: \nSelect and explain. \nA. Rickets, B. Chondrodystrophy, C. Osteoporosis, D. Hyperparathyroidism', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Contracted pelvis is alteration in size and/or shape of pelvis of sufficient degree so as to alter the normal mechanism of labour in an average size baby. It can be a result of malnutrition, diseases or injuries affecting the bone of pelvis or it can be due to any developmental defect.', 'role': 'assistant'}]