F: Why did you charge me so much? ,M: Well the first five kilometers are $6 and every extra kilometre costs you $3, it was 10 kilometres altogether. ,F: Oh, that's right.
(A) M: I am afraid I did not quite catch what you were saying. Please repeat it. (B) M: The 5 kilometres you ran would cost $21. (C) M: That's $21 altogether. (D) M: $60 altogether, please.
C