What angle is formed between a rhumb line and the meridians of longitude?

The correct answer, "Constant Angle," is based on the definition of a rhumb line, which is a type of navigational line that crosses all meridians at the same angle. This characteristic of maintaining a constant angle with meridians is what differentiates rhumb lines from great circles, which do not maintain a constant angle.

When navigating using a rhumb line, sailors and pilots can maintain a steady course, which simplifies navigation as the angle to the meridians remains unchanged throughout the journey. This consistency allows for easier plotting of a course over long distances.

In contrast, the other choices imply variability in the angle to the meridians, which does not characterize a rhumb line. Navigational methods that rely on the curvature of the Earth, such as great circles, can involve varying angles with the meridians, leading to increased complexity in navigation.