The correct answer is C. Infrared radiation and is invisible.
The human body emits a small amount of electromagnetic radiation, mostly in the form of infrared radiation. This radiation is invisible to the human eye, but it can be detected by infrared cameras. The amount of radiation emitted by the body varies depending on the person’s temperature, skin color, and other factors.
Ultraviolet radiation is a type of electromagnetic radiation that has a shorter wavelength than visible light. It is invisible to the human eye, but it can cause sunburn and other skin damage. Humans do emit a small amount of ultraviolet radiation, but it is not enough to cause any harm.
Visible radiation is the type of electromagnetic radiation that we can see with our eyes. It has a wavelength between 380 and 700 nanometers. The human body does emit a small amount of visible radiation, but it is too weak to be seen.
D is incorrect because humans do emit electromagnetic radiation.