Question

What was the Blank Check?

A promise from Germany that they would help Austria if Russia mobilized


Bosnia's obligation to Serbia to protect Serbia from Austria and Germany if attacked


A huge sum of money sent by Germany to Austria for war preparation


A telegram sent to Austria warning them about Russia's mobilization

Answer 1

A bank check is a check that you can buy from a bank in order to pay someone who is not willing to accept a personal check.

that was the definition so...

hopes that helped