A website currently has its navigation menu showing at the top of the webpages for all screen sizes. Initial user feedback indicated the navigation menu took up too much space on mobile devices. The organization has decided to remove the navigation menu for smaller screens. While testing the new UI$,$ the feedback stated that users on smartphones did not know how to navigate to different pages on the website.

What would you recommend to help improve the UX$?$ Select the best answer.

a$.)$

Add a message at the top of all the webpages to scroll to the bottom of the webpage to navigate the website.

b$.)$

Use responsive web design $($RWD$)$ to create a multilevel menu with the Home option being the only menu item visible when a user is on a smaller screen.

c$.)$

Add a hamburger button at the top of the screen that will expand the navigation menu when clicked on$.$

d$.)$

Display the navigation menu on the left side of the screen instead of the top.