What is the primary use of tracking radar?

The primary use of tracking radar is to detect altitude, direction, and ranged targets. Tracking radar systems are designed specifically to follow the movement of targets over time, allowing them to gather information on various parameters such as target speed, trajectory, and location in three-dimensional space. This capability is crucial in applications like air traffic control, military operations, and missile tracking, where maintaining accurate and continuous information about moving objects is essential.

The other options, while related to different functionalities of radar systems, do not align as closely with the main purpose of tracking radar. Detecting weather patterns, for example, is more specific to weather radars, which use a different operational method. Measuring distance for navigation is typically associated with other types of radar or navigation aids, and guiding missiles refers to specific systems that may use aspects of tracking radar but have broader operational requirements. Therefore, option B encapsulates the essence of what tracking radar is fundamentally designed to accomplish.