A. The precision and timing of the creeping barrage, repudiation of the traditional hierarchy in the British and French armed forces, observation and reconnaissance, and a new platoon organization that allowed for greater flexibility.
B. Medical advances like mobile blood banks, strict top-down command from British commanders, the threat of courts martial, waterproof boots to prevent trench foot.
C. Heavy artillery pulled by horses, a move away from tunneling and underground warfare, the use of flares during reconnaissance raids, and advances in the processing of soldiers at casualty clearing stations.
D. Frequent raids into No Man’s Land and enemy territory, prioritization of soldier’s well-being, effective use of balloons and blimps, use of detailed maps available to all ranks.