Uncheck RadioButtons

Hi there,

I have a question: is is possible to uncheck a radiobutton?

The form I´m working is to be filled electronically or if you want you can print it, so if by mistake you click on a radio I´d like to know if you can click it again to uncheck it (I know that you could close and open the form again, but you would have to fill it all again)

Any ideas?

Thanks!