Final answer:
The Japanese failed to achieve a total surprise attack because the Americans had cracked their top secret code.
Step-by-step explanation:
The correct answer is B. They failed to achieve a total surprise because Americans had cracked their top secret code.
While the Japanese made several mistakes during the attack on Pearl Harbor, such as failing to destroy any aircraft carriers and underestimating the effect of a surprise attack on the American people, their top secret code being cracked by the Americans was not one of those mistakes. This allowed the Americans to intercept and decipher important Japanese communications, giving them advanced knowledge of the attack.
By cracking the Japanese code, the Americans were able to anticipate the attack on Pearl Harbor to some extent and prepare for it, minimizing the element of surprise for the Japanese.
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