The correct answer is "Bertha".
Jane Eyre is a novel written by Charlotte Bronte in 1847. In a passage of the story, Jane, the protagonist, is currently at Thornfield Hall to work as a governess. While at that place, she discovers that her master, Mr. Rochester, has a secret wife named Bertha. Mr. Rochester proposes Jane to continue their plans to live together, after hearing this, Jane decides to leave the property. Upon her return, she sees that Thornfield Hall has been destroyed by a fire which she later learns was caused by Bertha.