The correct options are
B It spent most of the money and materials on war.
C It borrowed a lot of money from the USA.
D Unemployment increased due to decrease in demand.
Britain, which was a strong economy in the pre-war period, found itself facing a long economic crisis. In order to finance the war, Britain had borrowed a lot of money from the USA and was burdened with huge external debts. Britain focused its energies on the First World War. As the war ended, production decreased and unemployment increased.