In Act I of Arthur Miller's "The Crucible," Reverend Parris wants the doctor to find a natural cause for his daughter Betty’s illness because he believes that his congregation will drive him out of Salem if there is any talk of evil associated with his life or family.
Parris is primarily motivated by self-preservation and the fear of his reputation. He is acutely aware that any suggestion of witchcraft or evil linked to his household could jeopardize his position as the minister of Salem. Parris's concern is not just for his daughter's wellbeing, but also for the potential scandal that could arise from the situation, which he fears would lead to his ousting from the community.
Thus, the correct answer is: his congregation will drive him out of Salem if there is any talk of evil associated with his life or family.