What phenomenon causes X-ray attenuation?

X-ray attenuation is primarily caused by the absorption and scattering of X-ray photons as they travel through materials, such as human tissues. When X-ray beams pass through an object, they interact with the atoms in that object. Some of the photons are absorbed, which means they transfer their energy to the atoms, causing ionization or exciting electrons. Others may scatter, changing their direction but not necessarily losing energy.

The degree of attenuation depends on several factors, including the type of tissue the X-rays are passing through, the thickness of the material, and the energy of the X-rays. Denser tissues, such as bones, absorb more X-rays and therefore appear white on an X-ray image, while less dense tissues allow more X-rays to pass through, resulting in darker areas on the film.

The options related to light emission, reflection, and mechanical movement do not contribute to the attenuation of X-rays. Emission of light occurs in different contexts and is unrelated to how X-rays function. Similarly, reflection is a surface phenomenon that does not apply to the interaction of X-rays with matter in the same way as absorption and scattering. The mechanical movement of the X-ray machine is simply a factor in positioning but does not influence the physical interactions of X-ray photons