question: As shown in the figure, when the width of the water surface AB in the circular bridge hole is 8.0, the arc ACB is exactly a semicircle. When the water surface rises 1.0, the water surface width A′B′ in the bridge hole is ()
  Choices:
  A:√{15}米
  B:2√{15}米
  C:2√{17}米
  D:不能计算
query_wo: Please directly answer the question and provide the correct option letter, e.g., A, B, C, D.
  Question: As shown in the figure, when the width of the water surface AB in the circular bridge hole is 8.0, the arc ACB is exactly a semicircle. When the water surface rises 1.0, the water surface width A′B′ in the bridge hole is ()
  Choices:
  A:√{15}米
  B:2√{15}米
  C:2√{17}米
  D:不能计算
query_cot: Please first conduct reasoning, and then answer the question and provide the correct option letter, e.g., A, B, C, D, at the end.
  Question: As shown in the figure, when the width of the water surface AB in the circular bridge hole is 8.0, the arc ACB is exactly a semicircle. When the water surface rises 1.0, the water surface width A′B′ in the bridge hole is ()
  Choices:
  A:√{15}米
  B:2√{15}米
  C:2√{17}米
  D:不能计算
question_for_eval: As shown in the figure, when the width of the water surface AB in the circular bridge hole is 8.0, the arc ACB is exactly a semicircle. When the water surface rises 1.0, the water surface width A′B′ in the bridge hole is ()
  Choices:
  A:√{15}米
  B:2√{15}米
  C:2√{17}米
  D:不能计算