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: Pediatrics
A 2 year old boy has vitamin D refractory rickets. Investigations show serum calcium 9 mg/dl. Phosphate 2.4 mg dl, alkaline phosphate 1040 parathyroid hormone and bicarbonate levels are normal. The most probable diagnosis is – 
Select and explain. 
A. Distal renal tubular acidosis, B. Hypophosphatemic rickets., C. Vitamin D dependent rickets, D. Proximal renal tubular acidosis
B: Hypophosphatemic rickets.
Answer: B: Hypophosphatemic rickets. 
Explanation: None