Free Electrons Carry Heat in Metals Steps:

• Metals have delocalized electrons that move freely through the lattice structure.
• When heated, these electrons gain kinetic energy in hot regions.
• The free electrons diffuse from hot to cold areas, transferring energy via collisions.
• This rapid electron movement enables efficient thermal conduction.

Why C is correct:

• Free electrons in metals are mobile and carry kinetic energy directly from hotter to cooler regions, as per the electron gas model in solid-state physics.

Why the others are wrong:

• A: Electrons do not vibrate about fixed points; fixed vibrations describe lattice phonons in insulators, not metallic conduction.
• B: Protons are bound in nuclei and do not move; they cannot transport heat.
• D: Metal ions vibrate in place but do not move freely through the lattice; their motion contributes minimally compared to electrons.

Final answer: C