question: Hint: Please answer the question and provide the correct option letter, e.g., A, B, C, D, at the end.
  Question: As shown in the figure, the parallel lines a and b are intercepted by the straight line c. If ∠1 = 50.0, then the degree of ∠2 is ()
  Choices:
  (A) 150°
  (B) 130°
  (C) 110°
  (D) 100°