Which factor played the greatest role in making world war l one of the deadliest conflicts in human history?

I would say the invention of new technology such as the tank, machine guns, and other weapons made every attempt to gain yardage in trench warfare very bloody costing hundreds of lives for every yard gained or lost.

adopted the practice of proskynesis, a persian court custom that involved bowing down and kissing the hand of others, depending on their rank.

a

explanation: