(Open a book) is the answer to your question.
I'm gonna be completely honest, I didnt feel like going through all of those but it's really simple. if you use something like grammarly and type the sentences, it will correct your grammar so you can find out the answers :)
“Puddle-wonderful” is a made up word, a syntax. Syntax means “the arrangement of words and phrases to create well-formed sentences in a language.” So the author is describing the mud as wonderful.
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.
