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: Radiology
Which of the following is not done in a case of brain tumour? 
Select and explain. 
A. CT scan, B. MRI, C. X-ray skull, D. Lumbar puncture
D: Lumbar puncture
Answer: D: Lumbar puncture 
Explanation: Ans. Lumbar puncture