Final answer:
Shakespeare depicts evil and the supernatural mainly through characters committing dark deeds often influenced by the supernatural, as seen in plays like Macbeth and Hamlet, where characters are driven to evil actions due to prophecies or ghostly urgings, reflecting on the nature of morality and ethics.
Step-by-step explanation:
Shakespeare explores the theme of evil and the supernatural in his plays mainly by c) showcasing characters who resort to dark and deceitful methods to achieve their goals. For instance, Macbeth and Lady Macbeth orchestrate the murder of King Duncan, driven by their ambition and the prophecy of the witches, encapsulating the use of supernatural influence to commit evil acts.
The witches themselves, agents of the supernatural, manipulate Macbeth with their prophecies, highlighting the intertwining of evil actions with supernatural elements.
In Hamlet, the ghost of Hamlet's father spurs Hamlet into a quest for revenge, again combining the supernatural with the inclination to commit dark deeds. Additionally, the various plots of the plays often bring into question the moral fiber of characters, such as in the cases of Gertrude and Claudius, leading audiences to question the very nature of good and evil.
Furthermore, Shakespeare uses characters like Othello and Iago to delve into the psychological aspects of evil -- with Iago's manipulative schemes driving the narrative to a tragic end, demonstrating how jealousy and ambition can become corrupting forces.