Mark the letter A, B, C or D on your answer sheet to indicate the best arrangement of utterances or sentences to make a meaningful exchange or text in each of the following questions from 13 to 17.

a. Mark: Why online learning?
b. Ann: I think, I'll try online learning.
c. Mark: What are you going to do to get IELTS 7.0?
d. Mark: I think online platforms are too expensive. I don't think I'll try them.
e. Ann: Teachers are all native speakers, and they have flexible schedules.
(Adapted from Global Success)