Need Help: Creating quiz application prototype

I am creating a prototype for a javascript quiz application. There is question followed by multiple choice options. Each options has a button. I am using DOM and event to control the buttons.

I am trying to create function to group all the button together and validate each option that corresponds to the buttons. Right I have separate functions for each button/option. I need help/advice. Here is my project:

https://codepen.io/kola-aderinto/pen/EzKGKg?editors=1010

ahahah. lol. Well, I am learning JavaScript, and building apps is one the best ways to get better at JavaScript according to expert. Also, I am hoping to the a portfolio, and would like to showcase this project as part of my portfolio. I am glad am the 5th person that asked that same type of question, I guess I am not alone.