What is the low planning range of a SINCGARS radio?

The low planning range of a SINCGARS (Single Channel Ground and Airborne Radio System) radio is correctly identified as 200-400 meters. This range is significant because it represents the effective communication distance for troops operating in close proximity to one another, where radio communication is crucial for coordination and safety. The SINCGARS radio is designed for flexible and secure communications, allowing forces to maintain connection within a tactical environment, particularly at short distances.

The choice of 200-400 meters reflects the need for reliable communication in situations where troops are likely to be operating near each other, such as during reconnaissance or in urban combat scenarios. Understanding this range is essential for mission planning and executing effective operations, as it helps units determine when and how to utilize the SINCGARS radio effectively within its operational envelope.

In the context of the other options, configurations beyond 400 meters to 10 kilometers are generally associated with higher ranges for SINCGARS in secure communication modes but do not represent the low planning range. Therefore, the focus on the 200-400 meter range aligns with operational needs for close-combat communication, making it the correct choice.