Which of the following statements best describes early nazi military success during world war ii?

If your choices are the following:
A. The tactic created a stalemate between Great Britain and Germany on the western front.
B. The tactic's brutal total war techniques led the United States to declare war on Germany.
C. The tactic's reliance on speed and surprise led Germany to great success in the early years of the war.
D. The tactic shifted major German military battles from land conflicts to naval and aerial battles

Then I think thw answer is B.

What are the