Which of the following was a defining characteristic of total war during both world wars?

A. The start of an internal economic crisis

B. The huge number of military casualties

C. The spread of communist and fascist ideologies

D. The mobilization of entire populations for war efforts

A defining characteristic of total war during both world wars was that B - huge numbers of military casualties were present in both wars. These are casualties in the tens of millions in both wars. And that are only the military casualties, excluding the civil ones. What also happened to some extent in both wars was that entire populations were mobilized for war efforts - D. However, I would say that B is the most correct answer in this case.

Answer;

D. The mobilization of entire populations for war efforts

Explanation;

A defining characteristic of total war during both world wars was that the mobilization of entire populations for war efforts.

A total war is a war in which the entire nation is involved in. However, there are many ways in which an entire nation can be involved in a war. The following social, economical, military and political characteristics of a society/conflict signify a total war/society that wages a total war.