I think its option d. hope this helps :)
Answer:
.
Explanation:
If youre asking how it helped soldiers in ww2: It could have spread to the enemy spreading disease amongst enemy soldiers, most likely killing them after a while.
But if youre asking how it helped cause the war: It could have helped cause the war by all the unrest in the world at the time or people could have immigrated to enemy countries and spread the virus.
I believe it would be C good luck
