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, AB is the diameter of circle O, DB and DC are respectively tangent to circle O at points B and C. If ∠ACE = 25.0, then the degree of ∠D is ()
  Choices:
  (A) 50°
  (B) 55°
  (C) 60°
  (D) 65°