Is this question from the missionary story?
Is when a political candidate chooses a running mate, usually of the same party, with the goal of bringing more widespread appeal to the campaign.
The Treaty of Versailles meant peace at the times, as it ended the WWI. However, it also established very harsh conditions for Germany (high war reparations), which later led to Germany's poverty and the rize of Nazis to power : so it's blamed for instigating (causing, leading to) the WWII.
The Treaty of Versailles also brought a big land loss for Germany, Austria and Hungary.
B) The federal government must change its law.