Bulgarian opera singer Raina Kabaivanska looks on during her annual masterclass for young singers in Sofia Opera and ballet in Sofia on October 1, 2024. Raina Kabaivanska was one of the greatest sopranos of her generation -- arguably the greatest Tosca after Callas. And even at 89, the Bulgarian singer is still a force in opera. (Photo by Nikolay DOYCHINOV / AFP) (Photo by NIKOLAY DOYCHINOV/AFP via Getty Images)