This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax And Mediastinum, Subject name: Surgery
A 60-year-old woman, Sridevi presents with a murmur suggestive of mitral stenosis and an echocardiography confirmed a mass attached to the fossa ovalis of the left atrial septum. What is the most likely diagnosis? 
Select and explain. 
A. Cardiac myxoma, B. Endocarditis, C. Lymphoma, D. Metastatic cancer to the hea
A: Cardiac myxoma
Answer: A: Cardiac myxoma 
Explanation: Atrial myxoma is the most common benign cardiac tumor. It usually presents with symptoms of valvular obstruction (mural or tricuspid valve). It is attached by a pedicle to the fossa ovalis of the left atrial septum. It is treated by resection.