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: Pathology
Serum alkaline phosphatase level is normal in: 
Select and explain. 
A. Multiple myeloma., B. Paget's disease., C. Fibrous dysplasia., D. All of the above.
A: Multiple myeloma.
Answer: A: Multiple myeloma. 
Explanation: Serum alkaline phosphatase elevated in:
Paget's disease.
Fibrous dysplasia.
Hyper parathyroidism (Brown’s tumour)
Note: Serum alkaline phosphatase level is normal in multiple myelomaQ