question: Hint: Please answer the question and provide the correct option letter, e.g., A, B, C, D, at the end.
  Question: In the figure above, l || m. Which of the following must equal 180?
  Choices:
  (A) k + n + r
  (B) k + p + s
  (C) n + p + s
  (D) n + p + t