I think it’s b
I am sorry if I am wrong
<span>the leader that known as "ruler of all men," united the Mongol tribes and brutally conquered much of Muslim Asia was: D. Genghis Khan
Gengis Khan managed to united various Mongolian tribes that previously fight against each other, unite them, and lead them as a large viscious barbarian army.
During his reign, He managed to conquest allmost all parts of Asian continent and some parts of Eastern European Region</span>
Answer:
I believe it's D.
Explanation:
The US was kept in the dark about the extent of the atrocities committed during the Holocaust. Technically, the US did place an embargo on German good, but that was because of the war they were fighting against the Germans at the time, not really because of the Holocaust itself. After the war and more vivid details about the Holocaust were revealed, the US was heavily scrutinized for not getting more involved.

A war is only just if it is fought for a reason that is justified, and that carries sufficient moral weight. The country that wishes to use military force must demonstrate that there is a just cause to do so. ... Sometimes a war fought to prevent a wrong from happening may be considered a just war.