Read the sentence and study the table.

The women's club held fundraisers on a semiannual basis.

\begin{tabular}{|c|c|}
\hline
Prefix & Meaning \\
\hline
semi- & \begin{tabular}{c}
half in value; \\
happening once \\
halfway through a \\
specific time \\
period
\end{tabular} \\
\hline
\end{tabular}

Based on the definition of the prefix, what does the underlined word mean?

A. once a year
B. twice a year
C. twice a month
D. every other year