text: An aria in this opera strikes its lowest note, a C-natural, on the first syllable of the heavily accented phrase "l'ombre mostrarsi."
full_question: An aria in this opera strikes its lowest note, a C-natural, on the first syllable of the heavily accented phrase "l'ombre mostrarsi." Another aria in this opera is usually transposed down a whole step from F to E-flat, and was written explicitly for Fanny Tacchinardi Persiani. In this opera, the protagonist sings the aria "Regnava nel silenzio," in which she informs her maid Alisa that she has seen the ghost of a girl killed by her ancestor. The title woman of this opera sings "Il dolce suono" in a famous "mad scene" in which she fantasizes about her beloved Edgardo after murdering her husband Arturo. For 10 points, name this opera which was adapted from a Walter Scott novel, by Gaetano Donizetti.
first_sentence: An aria in this opera strikes its lowest note, a C-natural, on the first syllable of the heavily accented phrase "l'ombre mostrarsi."
raw_answer: Lucia di Lammermoor