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
Secondary hyperparathyroidism are seen in all except - 
Select and explain. 
A. Rickets, B. Osteomalacia, C. Osteoporosis, D. Renal failure
C: Osteoporosis
Answer: C: Osteoporosis 
Explanation: Primary -Singleadenoma(90%) Multipleadenomas(4%) Nodularhyperplasia(5%) Carcinoma(1%) Secondary -Chronicrenalfailure ,Malabsorption,Osteomalacia'and rickets Teiary DAVIDSONS PRINCIPLES AND PRACTICE OF MEDICINE 22ND EDITION PAGE NO-769