This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolic Disorders Leading to Osteosclerosis, Subject name: Orthopaedics
A 30 years female has lowr serum calcium and phosphate with elevated parathoramone. Diagnosis is - 
Select and explain. 
A. Vitamin D deficiency, B. Primary hyperparathyroidism, C. Osteoporosis, D. Paget's diseases
A: Vitamin D deficiency
Answer: A: Vitamin D deficiency 
Explanation: Ans. is 'a' i.e., Vitamin D deficiency o Vitamine D deficiency will have: -Low calciumLow phosphateHigh alkaline phosphataseHigh parathormone level (secondary hyperparathyroidism)About other optionso In primary hyperparathyroidism : -High calciumLow phosphateHigh alkaline phosphataseHigh parathormone levelo In osteoporosis all these parameters are normal.o In Paget's disease calcium and phosphate levels are normal. Serum alkaline phosphatase is raised.