Which of the following is classified as used military munitions?

The classification of military munitions often hinges on their status after use in activities such as testing, training, or combat operations. In this context, the correct answer pertains to the 40mm grenade that was fired in a function test.

When a munition like this grenade is used, even in a controlled function test, it qualifies as a used military munition because it has been discharged and is no longer in its original, unutilized state. The function test indicates that the munition has been actively employed in a testing scenario to ensure reliability and performance, thus solidifying its classification as "used."

On the other hand, options such as the 30mm cannon shell, the dummy grenade, and untested ammunition do not meet the criteria for being classified as used military munitions. The 30mm cannon shell, for instance, remains unused unless it has been fired in some capacity. The dummy grenade is designed for training and simulation purposes only and has not been operationally used. Similarly, untested ammunition has not been expended or assessed through any operation, meaning it cannot be classified as used.