Final answer:
The prophecies given by the witches in Act 4 have a significant impact on Macbeth's actions and decisions.
Step-by-step explanation:
The prophecies given by the witches in Act 4 have a significant impact on Macbeth's actions and decisions. They create a sense of uncertainty and indecision in Macbeth's mind, leading him to question his own ambition and reconsider his actions (c). The prophecies also fuel his already existing ambition and give him a newfound sense of confidence and determination (b). For example, when the witches tell him that 'none of woman born shall harm Macbeth,' it boosts his confidence and makes him believe that he is invincible.
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