The option that best characterizes the pardon-seller in The Canterbury Tales is devious.
In this story, the pardon-seller represents the dark side of the Medieval Church. He is devious, which means he deviates from doing good, because he behaves as an impostor. The pardon-seller uses dishonest methods, such as the selling of indulgences and pardons to sinners, in order to earn money. Although he is a church official, the pardoner is only driven by his ambition of making more money.