A 55-year-old male presents to the urgent care clinic with complaints of right ankle pain. The patient states that he was hiking earlier in the day and “twisted his ankle” as he was coming down an inclined slope. When asked to localize the maximal area of tenderness, he points to the lateral ankle. He is unable to weight bear and edema is present, surrounding the right ankle joint. Which of the following structures of the ankle was most likely injured?