Final answer:
The system described is a wired direct digital radiography (DR) system, which uses CMOS or CCD sensors to convert x-ray ionization into electrical signals, with instantaneous image display on a computer monitor.
Step-by-step explanation:
The description “The sensor is connected by a wire to the computer, and after exposure, the image appears instantly on the monitor” best fits the description of a wired direct digital radiography (DR) system. Direct digital radiography systems use solid-state detectors like CMOS or CCD sensors and are capable of converting the ionization produced by x-rays directly into an electrical signal. When these detectors are exposed to x-rays, they generate a stream of electrons, which are stored and counted at individual pixels. This information is then processed and displayed instantly on a computer monitor. Unlike PSP systems, which require an intermediate scanning step, DR systems provide an almost immediate image display.