Final answer:
Echocardiography images are made by using ultrasound waves that reflect off heart tissues, which are then processed by a computer to create real-time images of the heart. The correct option is c) Images are compiled from ultrasound reflected from the heart tissue.
Step-by-step explanation:
Echocardiography images are compiled from ultrasound reflected from the heart tissue. This imaging technique involves the transmission of high-frequency sound waves into the body to produce echoes when these waves bounce off the heart and its structures.
A computer then receives these echo signals and converts them into real-time images of the heart, showcasing how the heart muscles and valves are working. Multiple ultrasound sources in the probe's head are used, which are phased to constructively interfere in a specific, adjustable direction. As the beam is swept across the heart, echoes are measured by their position and depth, creating a detailed image that reveals the heart's shape and density.