Final answer:
C-4 in 'The Things They Carried' is a type of stable and moldable plastic explosive used in military operations during the Vietnam War.
Step-by-step explanation:
In “The Things They Carried,” by Tim O'Brien, C-4 refers to a type of plastic explosive that the soldiers would have carried. Used commonly by the military, C-4 is known for its stability and ease of use, which allows soldiers to shape and time the explosives for various tasks and demolitions while minimizing the risk of accidental detonation. This substance was particularly useful in the setting of the Vietnam War, where unconventional warfare often required the destruction of enemy supplies, clearing of obstructions, or the creation of traps and ambushes in the dense jungles.