Which of the following is an instrument for monitoring radiations:

Explanation

The Geiger-Mueller (GM) detector is a common portable instrument choice for a general laboratory radioactive material survey. GM detectors are capable of detecting alpha, beta, and gamma radiation. However, this instrument is limited by its ineffectiveness in detecting lower energy beta and gamma emitters. Radars send out electromagnetic waves as short pulses which may be reflected by objects in their path, in part reflecting to the radar. When these pulses intercept precipitation, part of the energy is scattered back to the radar. A cloud chamber, also known as a Wilson cloud chamber, is a particle detector used for visualizing the passage of ionizing radiation.