Hey there!
So, from looking at this question, the bottom or the ([tex]x[/tex]-axis) is [tex]how \ many \ games \ were \ rented[/tex]. So, this would mean that, the ([tex]y[/tex]-axis) would be (how much) each game would cost.
So, based from the option's listed above, the correct answer to this question would actually be (The cost of every 1 video game rented). This would be the main and the key point of this graph, how much each game would be.
You correct answer would be . . . . . .
[tex]\boxed{\boxed{The \ cost \ of \ every \ 1 \ video \ game \ rented}}[/tex]
Hope this helps.
~Jurgen