Final answer:
Increased systemic vascular resistance is the correct factor that increases afterload, which represents the resistance the heart must overcome to pump blood effectively.
Step-by-step explanation:
Afterload is increased by conditions that create higher resistance within the vascular system. Therefore, the correct answer to what increases afterload is (A) Increased systemic vascular resistance. This resistance is the force the ventricles have to overcome to pump blood effectively. When the resistance in the blood vessels increases, the heart must generate more force to open the semilunar valves and propel the blood through the aorta and pulmonary artery, thereby increasing the afterload. Factors such as increased aortic pressure can also contribute because they reflect the resistance the heart must overcome. High viscosity of the blood, increased length and diameter of the blood vessels and ventricular damage that causes increased resistance can also increase afterload.