jQuery - OnClick，在单击时始终更改表单元格的背景色

For example: You have a table, and it has 4 tds and 2 trs. Table's background color is white. If i click to A td, A td should be red, than if i click to B, B td should be red and A td should be red too. If i click to C than, C should be red and B and A should be red too.For example: You have a table, and it has 4 tds