D) foreshadowing, to create suspense by providing hints about the future.
Explanation:
The statement, “it’s easy to become anything you wish… so long as you’re willing to forfeit your soul” gives an hint of what is at stake in other to attain a future endeavor. It gives an indication of what the future holds given, an individual's sacrifice. This concept of given an hint or indication of the future could be described as a literary device called foreshadowing. The Chinese herbalist is using the statement to hint Jin Wang of what could possibly happen in the future.
