[TYPO3]How to associate tt_news categories with templates

[Reena]

Hi All,

I am using tt_news extension in my site.

I have created four categories.And all the four categories have different 
templates for single news display.I have created a single page where single 
news of all categories are displayed.

 But my problem is that single news of all categories are displayed at same 
page then how can I associate categories with different templates. So that 
if the single page is showing the news related to "Environment" category 
then the template related to that category gets displayed.

Your help would be highly appreciated.

Thank You.

Warm Regards,
Reena Chandel