Validator for checkbox on Client side

Hello guys 

I have a check box for a confirmation that a new member has read the terms
and conditions. This is an asp control, but can't seem to get a validator
control to reconize it. What is the best way to make this field so that it is
required to be checked on the client side?
asp.net 3.5)

Thanks

Please give me any suggestion .Help needed urgently
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