Answer:
The answer is C (to invite the reader to see the relevance of his subject).
Step-by-step explanation:
The author points out, with the questions, some changes that could have been unnoticed, because it's completely normal, but that can be seen now that he states it. Therefore, the topic becomes relevant because before the questions it wasn't. This is completely necessary because technology is a matter that no longer surprise people, as he says, everyone is now using phones and headphones, but when it's highlighted by a question it becomes new or discovered.