A or b there is no wrong answer
The answer is: A: It encouraged people to borrow money to buy stocks.
With the boom, banks began to give loans where they once had not. This risk of borrowing money from the bank was, in most people's view, a rewarding risk.
Because of imperialism, countries now had access to colonies. When the war started, they were able to equip their colonies to fight for their side. This led to higher tensions and increased involvement in the war.
