Final answer:
The medium known for moving easily over a surface to create lines with a sheen is the pencil. Pencils and silverpoint both create detailed lines and historical artwork, but pencils are more commonly used today for their versatility and erasability.
Step-by-step explanation:
The medium that moves easily over a surface, creating lines that have a characteristic sheen, is b. Pencil.
Pencils work in a similar manner to metalpoint, historically utilized for many of the same purposes. Metalpoint
drawings, like those done with silverpoint, involve a metal rod, often silver, used to make marks on a prepared surface.
As the metal is drawn across the surface, it leaves behind a trace that can have a sheen due to the metal's properties. An example of this would be drawings from the Renaissance period. However, it's important to note that pencils are more commonly used for their ease of handling, ability to erase and apply varied pressures for different shades.