How would one describe a surface that is marked with thin, narrow grooves?

A surface marked with thin, narrow grooves can be aptly described as "striated." The term "striated" originates from the Latin word "stria," which means "line" or "furrow." It specifically refers to something that has lines or grooves, making it ideal for describing a surface with such characteristics. This can apply to various contexts, such as geology, botany, or even art, where lines or grooves are evident.

The other options do not have a similar focus on grooves or lines. For instance, "sophomoric" refers to a lack of maturity or sophistication, "stantorian" describes a deep or powerful voice, and "runic" pertains to ancient writing systems, particularly those used for Germanic languages. None of these terms evoke the imagery or definition associated with grooves or lines, which is why "striated" is the most fitting choice for describing the specified surface.