Final answer:
In Shakespeare's play Macbeth, the part of the murder plot that Macbeth forgets is to leave the murder weapon with the guards to frame them.
Step-by-step explanation:
The part of the murder plot that Macbeth forgets is B. The murder weapon. In Act II, Scene II of Shakespeare's play Macbeth, Lady Macbeth is alarmed to discover that Macbeth has brought the daggers with him after murdering King Duncan, instead of leaving them with the guards to frame them for the murder.
Lady Macbeth then takes it upon herself to return the daggers to the crime scene and smear the guards with blood, completing the intended deception. In Shakespeare's play Macbeth, the part of the murder plot that Macbeth forgets is to leave the murder weapon with the guards to frame them.
In Shakespeare's play Macbeth, Macbeth forgets the details of the murder plot. After committing the murder, Macbeth becomes overwhelmed with guilt and paranoia. As a result, he becomes forgetful and shows signs of mental deterioration.