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.
It is precise imagery because its a detailed visual description
Well, it doesn't show your italics, but if I had to guess, if say A. Hope this helps