Which statement about the ventricles is correct?

• A. The right ventricle forms the apex
• B. The left ventricle lies behind the sternum
• C. The right ventricle lies behind the sternum; the left ventricle forms the apex
• D. Both ventricles form the apex

Answer: (C)

Understanding how the ventricles sit in the chest and which chamber shapes the apex is the key idea here. The apex, or the tip of the heart, is formed primarily by the left ventricle, which is the thick-walled chamber pushing blood to the systemic circulation. The right ventricle sits more anteriorly and directly behind the sternum, making the sternum a surface landmark overlying it. Because of this arrangement, the statement that the right ventricle lies behind the sternum and the left ventricle forms the apex is correct. The apex is not formed by both ventricles, and the left ventricle being described as behind the sternum is not the emphasis; the left ventricle’s role in forming the apex is what matters.