This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Medicine
[{'content': "Which of the following statements about Pseudohypoprathyroidismistrue- \nSelect and explain. \nA. Caused by 'Gain of!ftmction' inherited mutation in Gsa subunit, B. Decreased formation of cyclic GMP is observed, C. Decreased formation of Inositol triphosphate is observed, D. Decreased formation of c-AMP is observed", 'role': 'user'}, {'content': 'Answer: D \nExplanation: decreased urinary cyclic AMP responses to PTH , presumably with a post -GS alpha defect in adenyl cyclase stimulation ( Harrison 17 pg 2394)', 'role': 'assistant'}]