The answer is most likely 'now' as theyre saying it hadnt been available in all stores before this.
There are numerous facts she could include. She could write that they always consist of 14 lines and that they originated in Italy, created by Francesco Petrarch, but were later adapted for the Iambic Pentameter and became highly popular in England due to people like Shakespeare and Earl of Surrey.
Option D as they started with “some might think that” which means they are starting the opposing point, the counterarguement.
Dr. Lanyon has learned damaging new information about Dr. Jekyll. I know this because after Utterson asks if Lanyon has seen Dr Jekyll, his face changes and he says he never wants to see him again.