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: Anaesthesia
The following is not the differential diagnosis of an anterior mediastinal mass. 
Select and explain. 
A. Teratoma, B. Neurogenic tumor, C. Thymoma, D. Lymphoma
B: Neurogenic tumor
Answer: B: Neurogenic tumor 
Explanation: B i.e. Neurogenic tumor Neurogenic tumors (arising in posterior nerve structues) are the most common posterior mediastinal tumor but these do not occur in anterior mediastinumQ. And posterior mediastinum is the most common location for neurogenic tumors.