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 liver metastasis appear hypoechoic on Ultrasonography – 
Select and explain. 
A. Breast cancer, B. Colon cancer, C. Renal cancer, D. Mucinous adenocarcinoma
A: Breast cancer
Answer: A: Breast cancer 
Explanation: Metastases from Breast Cancer are typically hypo-echoic (Echopoor) on Ultrasonography.
Metastases from carcinoma colon and renal cell carcinoma are typically hyper-echoic (or echogenic) while metastasis from mucinous adenocarcinoma typically appears 'calcified'.