NO LINKS OR ELSE YOU'LL BE REPORTED! Please give me the correct answer.Only answer if you're very good at English.

What does "it" refer to? Choose the phrase that completes the sentence.

"Vamos,Javier, I'll teach you how to defeat your father.I promise,it will be very satisfying."While talking, Grandpop doesn't miss a beat in the game or the music.

I promise, _____ will be very satisfying.

A: teaching you the game
B: talking while we play
C: defeating your father​