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: Biochemistry
A 5 year old female patient complains of deformed shape of legs. Patient is a strict vegetarian. Lab investigations reveal elevated level of alkaline phosphatase. This patient may be suffering from deficiency of- 
Select and explain. 
A. Vitamin A, B. Vitamin B1, C. Vitamin C, D. Vitamin D
D: Vitamin D
Answer: D: Vitamin D 
Explanation: Deficiency of vitamin D causes rickets in children and osteomalacia in adults. The weight bearing bones are bent to form bow-legs. In rickets, the plasma level of calcitriol is decreased and alkaline phosphatase activity is elevated.
Satyanarayana- Biochemistry, 3rd edition, pg-127