This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Radiology
Which of the following is hypointense (dark) on T2-weighted MRI? 
Select and explain. 
A. CSF, B. Fat, C. Edema, D. Hard calcification
D: Hard calcification
Answer: D: Hard calcification 
Explanation: .