Final answer:
X-rays are best for imaging hard body structures like teeth and bones, as they can penetrate these structures. The denser the material, the darker the shadow produced by X-rays. X-rays are commonly used in medicine to detect breaks in bones and to image structures that differ in density.
Step-by-step explanation:
X-rays are best used to visualize hard body structures such as teeth and bones.
The ability of X-rays to penetrate matter depends on density, with denser materials blocking more x-ray photons and producing darker shadows.
X-rays are commonly used in medicine to detect breaks in bones and to image physiological structures that differ in density from surrounding material, such as tumors.