question: In triangle ABC above, AB = AC, E is the midpoint of line AB, and D is the midpoint of line AC. If AE = x, what is length BC?
  Choices:
  A.6
  B.8
  C.2*x
  D.4*x
  E.4*x^2
  
query_wo: Please directly answer the question and provide the correct option letter, e.g., A, B, C, D.
  Question: In triangle ABC above, AB = AC, E is the midpoint of line AB, and D is the midpoint of line AC. If AE = x, what is length BC?
  Choices:
  A.6
  B.8
  C.2*x
  D.4*x
  E.4*x^2
  
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: In triangle ABC above, AB = AC, E is the midpoint of line AB, and D is the midpoint of line AC. If AE = x, what is length BC?
  Choices:
  A.6
  B.8
  C.2*x
  D.4*x
  E.4*x^2
  
question_for_eval: In triangle ABC above, AB = AC, E is the midpoint of line AB, and D is the midpoint of line AC. If AE = x, what is length BC?
  Choices:
  A.6
  B.8
  C.2*x
  D.4*x
  E.4*x^2
  