Which statement describes the strategy germany followed after russia withdrew from the war?

a) germany ended submarine warfare in an effort to convince the united states to stay neutral.

b) germany resumed unrestricted submarine warfare to cut off supplies going to the allies.

c) germany invaded mexico as a means of distracting the united states from the fighting in europe.

d) germany appealed to the united states to become one of the central powers.

The statement that is true About the strategy that Germany used  after Russia withdrew from the war is :
Germany resumed unrestricted submarine.warfare to cutoff supplies going to the allies
The absence of Russia created a huge hole on Alliances defense.

In 911, a group of vikings lead by rollo besieged paris and chartres. after a victory near chartres on 26 august, charles decided to negotiate with rollo. the talks were led by hervé, the archbishop of reims. this resulted in the treaty of saint-clair-sur-epte, which granted rollo and his soldiers all the land between the river epte and the sea. it also granted him brittany, "for his livelihood". at the time, brittany was an independent land which france had not been able to conquer. in exchange, rollo promised the king his loyalty and military assistance when needed. also rollo also agreed to be baptised and to marry gisela, the king's daughter. the territory given rollo is about the same as upper normandy.