Final answer:
The prediction not made about Macbeth by the witches is that he would be the father of future kings; this was said to Banquo.
Step-by-step explanation:
The correct answer is a) Macbeth would be the father of future kings. This prediction was not made to Macbeth by the witches; instead, it was made to Banquo. The witches made three predictions to Macbeth: b) he would be the Thane of Cawdor, c) he would be the King of Scotland, and d) he was already the Thane of Glamis. The prediction about the fathering of kings was directed toward Banquo when the witches said, "Thou shalt get kings, though thou be none"; meaning Banquo's descendants would be kings but he would not.