What are smoke rounds primarily used for?

Smoke rounds are primarily used to provide cover for troop movements. When deployed, these rounds create a smoke screen that obscures the visibility of certain areas from the enemy's line of sight. This is particularly important in combat situations, as it allows troops to maneuver more safely without being detected or targeted by enemy fire. The smoke can also disorient the enemy and complicate their targeting efforts, thereby enhancing the safety and strategic advantage of the troops using the smoke cover.

The other options, while they may seem plausible in various contexts, do not accurately reflect the primary function of smoke rounds. For example, signaling enemy positions can be part of tactical communication strategies, but smoke rounds are not specifically designed for this purpose. Similarly, while illumination rounds do provide light for nocturnal operations, that is not the role of smoke rounds. Testing ammunition performance, although a critical component in ensuring reliability and effectiveness, does not align with the intended operational use of smoke rounds on the battlefield.