Which is the most likely explanation for the impact of world war 1

New job opportunities opened up for women during the war, allowing them to take on new roles and gain public appreciation. Women in the World War 1 were mobilized in an unprecedented number throughout the world. The vast majority of these women were recruited to work in munitions factories, greatly expanding civilian work to replace the recruited men. Thousands served in the armed forces in support roles. For instance, woman served as nurses, but in Russia some were in combat.

d is the best answer for this question.

geography

this is because warmer climates often don't get people sick from the flu and regions where it was often colder more people received the flu. hope this if you need more reasoning i am here to