Which type of convoy movement allows for the best passive defense against observation and attack?

Infiltration is recognized as the type of convoy movement that allows for the best passive defense against observation and attack. This method typically involves moving through terrain that is less likely to be observed, employing stealth and potentially using elements of terrain to conceal movement.

Infiltration is characterized by smaller, more dispersed units, which reduces the likelihood of detection by enemy forces. This approach is aimed at minimizing the enemy's ability to observe and track the movement of the convoy, thereby providing a tactical advantage.

Additionally, the use of natural cover and terrain features during infiltration further enhances the chances of remaining undetected. By moving in a manner that is less predictable and avoiding obvious routes, units can effectively decrease their risk of encountering enemy forces and being targeted.

In contrast, formations typically present a more visible structure that can be easier for the enemy to observe and engage. Static movements tend to remain in one place and do not provide any offensive or evasive actions against threats. March order can imply a more conventional and linear movement that may not take full advantage of terrain for concealment.