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...

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.

Question 13:

a.        Dad: Well, imagine if all bees disappeared tomorrow. No more flowers, no more fruits, no more food for animals...

b.        Alex: Oh, wow! So these little bees are like the most important workers in nature's big factory?

c.        Alex: Dad, why do they call bees "keystone species"? They're just tiny bugs!

A. a-c-b                                                B. c-b-a                                        C. b-a-c                                                D. c-a-b