Given this text: "Pindar is the first author to allude to the story in the surviving literature, remarking that the goddess turned herself into fire and a lion with sharp claws and fearsome teeth; but Peleus' capture of Thetis can be traced back to the seventh century BC in the visual arts, and her transformations are regularly indicated from the second half of the sixth century onwards.". Which cefr level fits best: A1, A2, B1, B2 or C1?
a1