Given levels: A1, A2, B1, B2 and C1. Which cefr level would you assign to: "Mention the Yellow Brick Road, the Wicked Witch of the West, or Emerald City, or hum a few notes of "Over the Rainbow" or "We're Off to See the Wizard," and Americans of all ages, races, and classes will catch the reference immediately, and with fondness."?
a1