What is the definition of the term "bench marks"?

The term "bench marks" refers to a surveyor's mark made on rocks or other permanent objects to indicate known elevations. This definition is associated with surveying and land measurement, where benchmarks serve as reference points for determining altitude or elevation above sea level. Such marks are crucial for various applications, including construction, land surveying, and geographical mapping, as they provide a consistent reference that can be used to ensure accuracy in measurements.

While options like a unit of measurement for nautical navigation, a type of map used in mountain climbing, or performance standards in education might seem relevant in different contexts, they do not align with the specific terminology associated with the term "bench marks" in surveying and elevation measurement. This specificity is what distinguishes option B as the correct choice.