Final answer:
Macduff informs Macbeth that he was born via Caesarean section, thereby negating the witches' prophecy and sealing Macbeth's fate.
Step-by-step explanation:
In Act 5, Scene 8 of Shakespeare's Macbeth, Macduff reveals to Macbeth an essential fact about his birth which directly impacts the prophesy Macbeth has been relying on for his sense of security. Macduff informs Macbeth that he was not of woman born in the usual sense, but was instead "from his mother's womb untimely ripp'd," meaning he was born via Caesarean section (C-section). This revelation is crucial as it negates the witches' prophecy that no man of woman born could harm Macbeth, thus sealing Macbeth's fate.
The correct answer is: A) Macduff reminds Macbeth that he was born through a C-section.