HTML table data, how to: <td class="selected">

Question

In one of the tasks in the HTML I found this line of code which is not working when I open it in any browser,
<td class="selected">Code</td>
I replaced this one with the below,
<td bgcolor="Indigo"><font color="white">Discuss</font></td>

can you tell why is the first one not working properly, this line of code should get the cell selected

Answer 1

do
style="background-color:indigo;color:white;"