Answer: C change become to became
Explanation: the sentence talks about something in the past so become is changed to past tense “became”
"A coherent narrative will be easy to follow and more enjoyable for your reader." Looking at this, we see the words, "easy to follow," and, "more enjoyable." These are our clue words. We can rule our both A, B and D because none fit in as a definition referring to easy. C, however, fits the definition and this is your answer.
"A 'connected' narrative will be easy to follow and more enjoyable for your reader."
I believe the answer is (B) because (A) has an improper use of the colon, and in (C) they put the semi colon after "we" which doesnt make sense because "We had a relaxing lunch we," is not a proper sentence.