What is a characteristic of both gamma rays and x-rays?

• A. No Ionizing Capability
• B. Requires Direct Contact
• C. High Penetration
• D. They Are Visible To The Eye

Answer: (C)

High-energy electromagnetic radiation that can pass through matter is the key idea. Gamma rays and x-rays are both very penetrating forms of radiation, which is why they can travel through tissue and many materials. This penetrating ability is what makes them useful for medical imaging and therapy, but it also means they can ionize atoms in their path, so they carry ionizing capability. They do not require direct contact to affect something, unlike particles that must touch the tissue. And they are not visible to the eye. So the best characterized shared trait is their high penetration through materials. Shielding with dense materials like lead is used to reduce exposure due to this penetrating nature.