Final answer:
The part of the heart that composes most of the anterior surface is the right ventricle. The ventricles are the main pumping chambers of the heart, with the right ventricle specifically pumping blood to the lungs. Option 3.
Step-by-step explanation:
The anterior surface of the heart is mostly composed of the right ventricle. When looking at the heart's anatomy, the right atrium and right ventricle make up the right side of the heart, while the left atrium and left ventricle compose the left side.
The ventricles are the heart's primary pumping chambers; the right ventricle pumps blood to the lungs, and the left ventricle pumps blood to the rest of the body.
The right ventricle can be identified by structures such as the tricuspid valve, chordae tendineae, trabeculae carneae, and papillary muscles that extend from the inferior ventricular surface.
Therefore, among the multiple-choice options given: 1) Right atrium, 2) Left atrium, 3) Right ventricle, 4) Left ventricle, the correct answer is the right ventricle (option 3).