Sahar Does Not Have Medical Insurance and Pays All Her

Sahar does not have medical insurance and pays all her medical bills out of pocket. Her demand schedule for chiropractic visits is shown in the table below.
$\begin{array}{|l|l|}\hline \text {Price, \$ per Visit }& \text {Number of Visits per Month} \\\hline 0 & 10 \\\hline 5 & 9 \\\hline 10 & 8 \\\hline 15 & 7 \\\hline 20 & 6 \\\hline 25 & 5 \\\hline 30 & 4 \\\hline 35 & 3 \\\hline 40 & 2 \\\hline 45 & 1 \\\hline 50 & 0 \\\hline\end{array}$
-With insurance, at the $50 office visit price, the welfare loss to society due to moral hazard (if any) in Sahar's case is

A) $400.
B) $320.
C) $180.
D) $80.
E) $0.