The resistance to motion created when one surface rubs against another is called:

The correct answer is friction. Friction is the force that opposes the relative motion between two surfaces in contact. When one surface slides over another, the microscopic roughness of the surfaces interacts, creating resistance to motion.

Friction is crucial in various applications; it allows vehicles to stop when brakes are applied and helps in walking, as it provides the necessary grip between shoes and the ground. Different types of friction, such as static, kinetic, and rolling, describe the resistance depending on whether the surfaces are stationary, sliding, or rolling relative to each other.

The other options refer to different concepts which do not fit the definition of resistance to motion created by surface contact. Thermal conductivity relates to the ability of a material to conduct heat, drag pertains to the resistance experienced by an object moving through a fluid (like air or water), and thrust refers to the forward force produced by engines or propellers to propel objects. These terms do not capture the specific nature of the resistance caused by direct contact between solid surfaces.