What type of radiation can pass through most objects, including the human body?

X-rays are a form of electromagnetic radiation that have the ability to penetrate various materials, including living tissues. This property is due to their relatively high energy and short wavelength, which allows them to pass through substances that absorb lower energy radiation, such as alpha and beta particles.

When X-rays pass through the human body, they can reveal images of bones and internal organs because different tissues absorb X-rays to varying degrees. For instance, denser materials like bones absorb more X-rays and appear white on an X-ray film, whereas softer tissues allow more X-rays to pass through and appear darker. This capability is widely utilized in medical imaging to diagnose and monitor health conditions.

In contrast, alpha particles are heavy and carry a positive charge, making them unable to penetrate the outer layer of human skin or even paper. Beta particles can penetrate skin but are still limited in their ability to pass through dense materials. Gamma rays, while also capable of penetrating objects, are often associated with radioactive processes and are typically more penetrating than X-rays. However, the specific context of the question aims at identifying the commonly used form of radiation in medical imaging, which is X-rays.