What type of radiation has lower energy and cannot ionize atoms?

Nonionizing radiation is characterized by its lower energy levels, which are insufficient to remove tightly bound electrons from the orbit of an atom. This means that it does not have the capability to ionize atoms, thereby not causing the chemical changes associated with ionization. Examples of nonionizing radiation include radio waves, microwaves, and visible light, all of which can affect matter in other ways but do not have the high energy necessary to directly ionize atoms.

Ionizing radiation, on the other hand, carries enough energy to ionize atoms, which can lead to cellular damage and has associated health risks. Thermal radiation involves the emission of energy in the form of infrared radiation and is closely linked to temperature, while chemical radiation is not a standard classification in radiation types. Thus, the defining quality of nonionizing radiation as being incapable of ionization makes it the correct answer in this context.