On the graph below, the buffering region is indicated by Roman numeral $*$

$1$ point

Ethanoic acid $($vinegar$)$ has a variety of uses. To ensure that production plants meet concentration specifications, technicians monitor the concentration of the acid by titrating samples of the ethanoic acid as it comes off the production line.

Titration of $10\mathrm{.}0mL$ of $C{H}_3\frac{C}{O}OH(aq)$ with $0\mathrm{.}20mo\frac{l}{L}$NaOH$(aq)$

IV

I

II

III