Final answer:
The apex of the heart is aligned with the Left fifth intercostal space. It is located just to the left of the sternum, reflecting its slight leftward deviation within the thoracic cavity.
Step-by-step explanation:
The apex of the heart is typically found on a line drawn vertically downward from the C) Left fifth intercostal space. The apex lies just to the left of the sternum between the junction of the fourth and fifth ribs near their articulation with the costal cartilages.
The heart is located within the thoracic cavity, primarily between the lungs in the mediastinum. It is protected by the pericardium and sits within the pericardial cavity. The orientation of the heart is such that its apex is deflected slightly toward the left side of the body. This deviation is particularly important when it comes to medical examinations and imaging, and it corresponds with the cardiac notch depression in the medial surface of the left lung's inferior lobe.