What characterizes a rhumb line?

A rhumb line, also known as a loxodrome, is characterized by its property of crossing all meridians at the same angle. This means that as a vessel or aircraft follows a rhumb line, it maintains a consistent compass direction, allowing for easier navigation since the heading does not need to be adjusted constantly. The main advantage of a rhumb line in navigation is its simplicity; the navigator can set a course and maintain that course using a consistent heading without the complexities that arise from changing angles of approach as one moves across the surface of the Earth.

The other options do not adequately represent the unique attributes of a rhumb line. While it may seem appealing to consider the shortest distance between two points or a straight line on a globe, these descriptions actually pertain to a great circle route, which is the shortest path between two points on a sphere. However, a rhumb line does not offer the shortest distance and is not a straight line in the sense that it curves in relation to the surface of the Earth, although it does maintain a constant angle to the meridians. Therefore, the defining characteristic of a rhumb line remains its ability to cross all meridians at the same angle, facilitating straightforward navigation across long distances