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: Medicine
Hypophosphatemia is a caused by 
Select and explain. 
A. Primary hypothyroidism, B. Primary hyperparathyroidism, C. Primary hyperthyroidism, D. Hypoparathyroidism
B: Primary hyperparathyroidism
Answer: B: Primary hyperparathyroidism 
Explanation: None