What does a declination refer to in geometry?

In geometry, a declination specifically refers to the angle between the perpendicular to a surface and a line along that surface. This concept is particularly relevant in fields such as surveying and climate science, where understanding the orientation and angle of surfaces is crucial. When measuring declination, one is assessing how much the line deviates from being perfectly perpendicular to that surface. This definition aligns with the context of the question, emphasizing the importance of angular relationships in geometric interpretations of real-world scenarios.

The other options describe different geometric concepts, such as altitude, the angle between intersecting lines, and relationships among angles in triangles, which are unrelated to the specific definition of declination. Understanding these distinctions clarifies the application of geometric principles across various fields.