What does bearing refer to in surveying?

In surveying, bearing is defined as the direction or angle of a line with respect to a meridian, which is typically either true north or magnetic north. This means that the correct answer emphasizes the relationship between the directional line being measured and the established north direction used as a reference.

Bearing can be expressed in degrees, minutes, and seconds or in cardinal directions (such as N, S, E, W) combined with an angle (for example, N 30° E). This system allows surveyors to communicate precise direction and orientation of points relative to the earth's coordinate system, which is essential for accurate mapping, construction, and land development.

The other options do not accurately describe the definition of bearing in surveying. The distance to a specific point relates to measurement rather than orientation. The angle made with the vertical line describes a different aspect of geometry, often referred to as slope or inclination, not bearing. The curvature of the earth’s surface pertains to geodesy and adjustments for large scale surveys but does not define bearing itself. Thus, understanding bearing as a means of indicating direction and reference to a meridian is crucial in surveying practices.