challenge: How are features identified on lunar maps in relation to the crater Polzunov?
  
  A. By placing the letter at the rim of the crater Polzunov
  B. By placing the letter on the side of the crater midpoint that is farthest from Polzunov
  C. By placing the letter at the center of the crater Polzunov
  D. By placing the letter on the side of the crater midpoint that is closest to Polzunov
  Answer: 