What Did the British and Allies Incorrectly Assume, Leading to Their

What did the British and Allies incorrectly assume, leading to their plan for the Big Push?

A) Infantry and artillery attacks were no longer effective.
B) The use of tanks would constitute a significant advantage.
C) A massive number of men and explosives would make a breakthrough possible.
D) Using minimal explosives and manpower would surprise the Germans.
E) Germany's military strength had been greatly depleted by the British blockade.