Final answer:
Macbeth is largely confident going into his final battle due to the prophecy he received, which stated he could not be defeated by any man born of a woman. His belief in his military skills and past successes also played a role.
Step-by-step explanation:
The main reason Macbeth is so confident going into his final battle in Shakespeare's play Macbeth is due to the prophecy he received. This prophecy told him that he could not be defeated by any man born of a woman (B). Macbeth believes this prophecy protects him from any harm in battle, so he charges confidently into his final fight.
Additionally, his belief in his military skills and past successes (A and D) may have contributed to his overconfidence. However, these reasons are not the primary cause of his assuredness. His confidence stems primarily from the prophecy he has received.
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