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: Unknown
[{'content': 'Which of the following tend to show marked and homogeneous enhancement on Gd-DTPA enhanced MRI? \nSelect and explain. \nA. Meningiomas and acoustic neuromas, B. Oligodendrogliomas and Metastases, C. Meningiomas and low grade gliomas, D. Glioblastoma multiformies and acoustic neuromas', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Meningiomas and acoustic neuromas tend to show marked and homogeneous enhancement 0." Gd-DTPA-enhanced MRI Ring-shaped contrast enhancement occurs in most glioblastoma8, whereas low-grade gliomas may show lack of changes on postcontrast images or only patchy enhancement.\nDepending on tumor size, metastases present as small homogeneously enhancing lesions or as ring-shaped structures secondary to central necrosis, which adds to the hallmark of metastatic tumors (i.e., multiplicity of lesions).', 'role': 'assistant'}]