Answer:
A. Warfare was far deadlier than in the past and resulted in enormous casualties
Step-by-step explanation:
No one would have dared to predict the casualties of World War I. When World War I was declared there were street celebrations in most of Europe’s capital cities. No one even envisaged trench warfare in August 1914 let alone the appalling casualties that occurred over 4 years of fighting. No one could have predicted the horrifying consequences of modern weaponry being used together with out-of-date tactics. The grim figures ‘speak’ for themselves. The estimated number of people killed during World War I varies from 8.5 to 12.0 million.