B - agenda
An agenda is what the author really wants to point out (their underlying message) and it's typically written in a way where it's somewhat hidden. Example: political ads - they have an agenda for what they want to talk about and why it's important.
He wants to tell the audience that he did not achieve all of his goals. He wants to let the audience know that mastering the basics is key to achieving goals. He wants to explain how to be a good football coach to people who are interested in football.
Answer: Susan
Explanation: Susan is the second oldest sibling. She does not believe in Narnia until she actually goes there.
