Which parts of the cardiovascular system are responsible for collecting oxygen-rich blood?

The left atrium, left ventricle, and arteries are the key components of the cardiovascular system that are involved in collecting and distributing oxygen-rich blood throughout the body.

The left atrium receives oxygen-rich blood from the lungs through the pulmonary veins. Once the left atrium is filled with oxygenated blood, it contracts to push the blood into the left ventricle. The left ventricle is responsible for pumping this oxygen-rich blood into the aorta, from which it is distributed to the rest of the body through various arteries. This process is vital for delivering the oxygen and nutrients that tissues and organs require for proper functioning.

The other options include components of the cardiovascular system, but they do not focus on the collection of oxygen-rich blood. For instance, the right side of the heart (right atrium and right ventricle) deals with deoxygenated blood returning from the body. Veins and capillaries are primarily involved in returning blood to the heart and not specifically in collecting oxygen-rich blood. Therefore, the choice highlighting the left atrium, left ventricle, and arteries correctly identifies the structures responsible for this essential function in the circulatory system.