What happens to an accelerated liquid

[sparkle123]

Hello,
I have no idea how to do the attached problem. Could you please help me out?
Thanks!

 

[kushan]

hey sparkle , think what happens when a small marble is but in the bcentre of a box and then the box is accelerated ?

 

[sparkle123]

hi kushan! the marble seems to roll back (relative to the box) due to inertia? but then wouldn't (d) be the right answer, if the water is "rolling back"?
thanks! :)