A reference mark from which vertical measurements are made is known as a?

A reference mark from which vertical measurements are made is known as a Bench Mark. In surveying and construction contexts, a bench mark is a permanent physical marker that indicates a specific elevation or point of reference. These markers are essential for ensuring accuracy in measurements, such as when establishing ground levels for foundations or determining the height of structures.

The value of a bench mark lies in its ability to provide a stable and reliable point for taking vertical measurements across different locations, thus facilitating consistent levels for various construction or engineering tasks. The usage of bench marks allows surveyors and engineers to maintain precision and uniformity in their work. Bench marks can be found in a variety of forms, such as metal discs or engraved stones, and they are usually placed at well-defined, easily identifiable locations.

Other options like a Level Point or Measurement Reference may convey related concepts, but they do not specifically designate the established and widely recognized reference used for vertical measurements that a bench mark provides.