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
Which of the following is seen in secondary hyperparathyroidism is 
Select and explain. 
A. Chronic hypercalcaemia, B. Chronic hypocalcaemia, C. Chronic hypomagnaesemia, D. Chronic hypermagnaesemia
B: Chronic hypocalcaemia
Answer: B: Chronic hypocalcaemia 
Explanation: None