The Following Table Shows the Number of Dog Collars, in Thousands

Multiple Choice

The following table shows the number of dog collars, in thousands, produced by Allied Pet Products in the three years considered. For a function of the form $f ( x ) = a x ^ { 2 } + b x + c$ that fits this data, what is the value of c?
$\begin{array} { c | c } \text { Year } & \begin{array} { c } \text { Number of dog collars } \\\text { (in thousands) }\end{array} \\\hline 0 & 20 \\\hline 6 & 14 \\\hline 18 & 23.6\end{array}$

A) 23.6
B) 14
C) 20
D) 12.8