Question

What evidence suggests that the dagger macbeth sees is an illusion

Answer 1

D. A false creation/ Proceeding from the heat-oppressed brain.
This answer suggests that it could have been an illusion by saying it might have been a "false creation" and that it could have came from his "heat-oppressed brain."

Answer 2

In this passage from Act II, Scene I, "The Tragedy of Macbeth", by William Shakespeare, the statement that suggests that the dagger is an illusion is option D. A false creation, / Proceeding from the heat-oppressed brain? Macbeth, before killing King Duncan, sees a dagger in the air with its handle towards him and its tip towards Duncan. He doesn't know whether it is real or not.