Hi, I've tried doing:
1)
<select size="20" class="selectionConfig" style="width:100%; text-align:center">
<%
for(int i=0;i<PowerTable.length;i++)
{%>
<option style="background-color:#C2E7D2">
<%=PowerTable[i][0]%>
</option>
<%}%>
</select>
2)
<select size="20" class="selectionConfig" style="width:100%">
<%
for(int i=0;i<PowerTable.length;i++)
{%>
<option style="background-color:#C2E7D2; text-align:center">
<%=PowerTable[i][0]%>
</option>
<%}%>
</select>
3)
<select size="20" class="selectionConfig" style="width:100%">
<%
for(int i=0;i<PowerTable.length;i++)
{%>
<option style="background-color:#C2E7D2; text-align:center">
<font style="text-align:center"><%=PowerTable[i][0]%></font>
</option>
<%}%>
</select>
But not is possible