Final answer:
A Geiger counter is the device that uses a clicking sound to indicate the intensity of radiation, with the frequency of the clicks increasing with higher radiation levels. Option A) Geiger counter is the correct answer.
Step-by-step explanation:
A Geiger counter is a type of radioactive device that indicates the intensity of radiation with a clicking sound that increases in frequency as more radiation is present. It is based on the Geiger-Müller tube, which contains a conducting cylinder with a wire along its axis and is filled with an insulating gas. Ionizing radiation passing through the tube produces free ion pairs that are detected as a count, producing a clicking sound.
The radioactive device that indicates the intensity of radiation with a clicking sound, which increases as more radiation is present, is known as a Geiger counter. The Geiger counter uses a Geiger-Müller tube where ionizing radiation ionizes the gas inside, creating ion pairs and a subsequent current that is detected and counted. This clicking noise is an audio output indicating the rate of ionization and thus the relative intensity of radiation. Other devices for detecting radiation include scintillation counters and radiation dosimeters, but for the specific description given, the correct option is a Geiger counter.