Which characteristic describes the M4A1 Carbine?

The M4A1 Carbine is accurately described as gas operated, air cooled, and magazine-fed. This configuration allows the weapon to cycle automatically by using the gas produced from fired cartridges to eject the spent cartridge case and chamber a new round. The air cooling system helps in managing the heat generated during sustained fire, making it effective for rapid engagements without overheating. The magazine-fed characteristic indicates that the M4A1 uses detachable magazines to feed ammunition into the chamber, which enhances its versatility and ease of reloading during combat situations. These features come together to make the M4A1 a reliable and efficient firearm for military use.