Final answer:
In Act IV, Reverend Parris undergoes a significant change in his character as he becomes more desperate to protect his own name and reputation. He becomes more self-interested and fearful.
Step-by-step explanation:
In Act I of the play, Reverend Parris is introduced as a strict and authoritative figure. He is deeply concerned about his reputation and the well-being of his daughter, Betty. However, in Act IV, Parris undergoes a significant change in his character.
By this point in the play, Parris has witnessed the chaos and tragedy caused by the witch trials. He becomes more desperate to protect his own name and reputation, and becomes paranoid that the townspeople will turn against him. He is willing to do anything to save himself, even going so far as to defend Proctor and Elizabeth when previously he had been accusing them.
This change in Parris's character reflects the overall shift in the town of Salem. As the hysteria surrounding witchcraft intensifies, Parris begins to see the consequences of his actions and becomes more self-interested and fearful.