This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pancreas, Subject name: Surgery
Most common primary leading to secondaries in pancreas;- 
Select and explain. 
A. Lung, B. Breast, C. Colon, D. Stomach
A: Lung
Answer: A: Lung 
Explanation: Metastatic tumors to pancreas MC site of primary: RCC > malignant melanoma On autopsy, MC site of primary: Ca lung