For These Data, What Is the Three-Period Trailing Moving Average

Multiple Choice

For these data, what is the three-period trailing moving average for period 6? $$\begin{array} { | c | c | c | c | c | c | c | c | c | c | } \hline t & 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 & 9 \\\hline y _ { t } & 22 & 33 & 27 & 34 & 38 & 26 & 28 & 35 & 41 \\\hline\end{array}$$

A) 32.67
B) 31.33
C) 33.00
D) 34.67